Remove unused createEventFlag function am: 1390abc07c am: 651a52f908 am: 6d587ab3b6 am: 3629887c11

Original change: https://android-review.googlesource.com/c/platform/system/libfmq/+/1792489

Change-Id: I70822ca2b29ddd6d7eb48560a11da552709e0422
tree: a5c224cbb5a5e69d6d2424c398b91cd780ed0b0d
  1. base/
  2. benchmarks/
  3. fuzzer/
  4. include/
  5. tests/
  6. Android.bp
  7. EventFlag.cpp
  8. FmqInternal.cpp
  9. OWNERS
  10. PREUPLOAD.cfg
  11. TEST_MAPPING