embind-emit-tsd does not work with -sMEMORY64

Please include the following in your bug report:

**Version of emscripten/emsdk:**
3.1.47

**Failing command line in full:**

After adding `--experimental-wasm-memory64` to `.emscripten`.

```
em++ -fwasm-exceptions -lembind -sMEMORY64 ./test/other/embind_tsgen.cpp --embind-emit-tsd=foo
em++: warning: -sMEMORY64 is still experimental. Many features may not work. [-Wexperimental]
/tmp/emscripten_temp_kgu18wx6/tsgen_a.out.js:136
throw ex;
^

Error: Missing primitive type to TS type for 'unsigned long'
at TsPrinter.typeToJsName (/tmp/emscripten_temp_kgu18wx6/tsgen_a.out.js:2503:19)
at FunctionDefinition.printSignature (/tmp/emscripten_temp_kgu18wx6/tsgen_a.out.js:1511:39)
at FunctionDefinition.printFunction (/tmp/emscripten_temp_kgu18wx6/tsgen_a.out.js:1519:14)
at ClassDefinition.print (/tmp/emscripten_temp_kgu18wx6/tsgen_a.out.js:1430:18)
at TsPrinter.print (/tmp/emscripten_temp_kgu18wx6/tsgen_a.out.js:2516:15)
at embindEmitTypes (/tmp/emscripten_temp_kgu18wx6/tsgen_a.out.js:2535:15)
at callRuntimeCallbacks (/tmp/emscripten_temp_kgu18wx6/tsgen_a.out.js:1002:26)
at initRuntime (/tmp/emscripten_temp_kgu18wx6/tsgen_a.out.js:465:3)
at doRun (/tmp/emscripten_temp_kgu18wx6/tsgen_a.out.js:3096:5)
at run (/tmp/emscripten_temp_kgu18wx6/tsgen_a.out.js:3117:5)
em++: error: 'node --experimental-wasm-eh --experimental-wasm-memory64 /tmp/emscripten_temp_kgu18wx6/tsgen_a.out.js' failed (returned 7)

```