Android ld.bfd 2.25 adds PT_INTERP, breaking injection

See this thread: https://groups.google.com/forum/#!topic/dynamorio-users/eL1__o7m4AQ

Summary:

A custom-built DR hits this assert:

```
$ adb shell /data/local/tmp/build_android/bin32/drrun -debug -- /data/local/tmp/hello

```

It's due to PT_INTERP in libdynamorio:

```
% readelf -l lib32/release/libdynamorio.so
INTERP 0x000114 0x00000114 0x00000114 0x00013 0x00013 R 0x1
[Requesting program interpreter: /system/bin/linker]
```

This is 2.25:

```
% android-ndk-21/bin/arm-linux-androideabi-ld --version
GNU ld (binutils-2.25-48ba864) 2.25.51.20141117
```

Our release packages are built with:

```
GNU ld (GNU Binutils) 2.24.90
```