static linking fails - ar: libdeps specified more than once

When building https://github.com/snikket-im/snikket-sdk with this patch:

```
diff --git a/cpp.hxml b/cpp.hxml
index 1b039f6..d0fe0e8 100644
--- a/cpp.hxml
+++ b/cpp.hxml
@@ -14,4 +14,4 @@ snikket.persistence.Sqlite
--cpp cpp
-D HXCPP_NO_CPP11
-D HaxeCBridge.name=snikket
--D dll_link
+-D static_link
```

I get the following error:

```
Compiling group: hxcpp_sqlite
c++ -I/home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/hxcpp/git/project/thirdparty/sqlite-3.40.1 -c -fvisibility=hidden -O2 -fpic -fPIC -Wno-overflow -DHX_LINUX -DSTATIC_LINK(static) -DHXCPP_M64 -DHXCPP_VISIT_ALLOCS(haxe) -DHXCPP_ALIGN_ALLOC(haxe) -DHX_SMART_STRINGS(haxe) -DHXCPP_API_LEVEL=430(haxe) -m64 -DHXCPP_M64 -I/home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/hxcpp/git/include ... tags=[haxe,static]
- /home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/hxcpp/git/project/thirdparty/sqlite-3.40.1/sqlite3.c []
- Sqlite.cpp
Link: liboutput.a
ar: libdeps specified more than once
/home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/datetime/3,1,4/src/datetime/DateTime.hx:34: characters 1-7 : Warning : (WDeprecatedEnumAbstract) `@:enum abstract` is deprecated in favor of `enum abstract`
/home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/datetime/3,1,4/src/datetime/DateTime.hx:49: characters 1-7 : Warning : (WDeprecatedEnumAbstract) `@:enum abstract` is deprecated in favor of `enum abstract`
/home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/datetime/3,1,4/src/datetime/DateTime.hx:69: characters 1-7 : Warning : (WDeprecatedEnumAbstract) `@:enum abstract` is deprecated in favor of `enum abstract`
/home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/tink_http/0,10,0/src/tink/http/Header.hx:201: characters 1-7 : Warning : (WDeprecatedEnumAbstract) `@:enum abstract` is deprecated in favor of `enum abstract`
/home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/tink_http/0,10,0/src/tink/http/Protocol.hx:3: characters 1-7 : Warning : (WDeprecatedEnumAbstract) `@:enum abstract` is deprecated in favor of `enum abstract`
/home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/http-status/1,3,1/src/httpstatus/HttpStatusCode.hx:3: characters 1-7 : Warning : (WDeprecatedEnumAbstract) `@:enum abstract` is deprecated in favor of `enum abstract`
/home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/tink_http/0,10,0/src/tink/http/Method.hx:3: characters 1-7 : Warning : (WDeprecatedEnumAbstract) `@:enum abstract` is deprecated in favor of `enum abstract`
/home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/tink_http/0,10,0/src/tink/http/Fetch.hx:26: characters 10-22 : Warning : (WDeprecated) use Future.irreversible() - or better yet: new Future()
/home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/tink_http/0,10,0/src/tink/http/clients/SocketClient.hx:22: characters 12-24 : Warning : (WDeprecated) use Future.irreversible() - or better yet: new Future()
/home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/tink_http/0,10,0/src/tink/http/clients/StdClient.hx:19: characters 12-24 : Warning : (WDeprecated) use Future.irreversible() - or better yet: new Future()
/home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/tink_streams/0,4,0/src/tink/streams/Stream.hx:408: characters 12-24 : Warning : (WDeprecated) use Future.irreversible() - or better yet: new Future()
/home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/tink_io/0,9,0/src/tink/io/StreamParser.hx:45: characters 14-26 : Warning : (WDeprecated) use Future.irreversible() - or better yet: new Future()
/home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/tink_streams/0,4,0/src/tink/streams/Stream.hx:717: characters 26-38 : Warning : (WDeprecated) use Future.irreversible() - or better yet: new Future()
/home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/tink_streams/0,4,0/src/tink/streams/Stream.hx:696: characters 12-24 : Warning : (WDeprecated) use Future.irreversible() - or better yet: new Future()
/home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/tink_io/0,9,0/src/tink/io/std/InputSource.hx:15: characters 11-23 : Warning : (WDeprecated) use Future.irreversible() - or better yet: new Future()
/home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/tink_io/0,9,0/src/tink/io/std/OutputSink.hx:23: characters 56-68 : Warning : (WDeprecated) use Future.irreversible() - or better yet: new Future()
/home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/tink_streams/0,4,0/src/tink/streams/Stream.hx:593: characters 12-24 : Warning : (WDeprecated) use Future.irreversible() - or better yet: new Future()
/home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/tink_streams/0,4,0/src/tink/streams/Stream.hx:448: characters 7-19 : Warning : (WDeprecated) use Future.irreversible() - or better yet: new Future()
/home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/tink_streams/0,4,0/src/tink/streams/Stream.hx:650: characters 12-24 : Warning : (WDeprecated) use Future.irreversible() - or better yet: new Future()
/home/anjan/code/aports/testing/snikket-sdk/src/snikket-sdk-72a19608040ab5633e85f599370b6e8f8156d023/tink_streams/0,4,0/src/tink/streams/Stream.hx:671: characters 11-23 : Warning : (WDeprecated) use Future.irreversible() - or better yet: new Future()
Error: Build failed
```

Issue has been reported to downstream repo: https://github.com/snikket-im/snikket-sdk/issues/45

Start by reproducing the build with the static_link change in cpp.hxml and inspect the hxcpp_sqlite archive step that reports “ar: libdeps specified more than once.” Compare the static-link path with the working dll_link path, using the downstream snikket-sdk issue as context. Done means the static build completes without the duplicate libdeps error.

Written by the indexing model from the issue text.