Remove ndk_platform backend. Use the ndk backend. am: 45eee70204 am: f9e6fe8d5f am: 0e024c319e

Original change: https://android-review.googlesource.com/c/platform/system/libfmq/+/1778411

Change-Id: Ia0c9d738831fee8ee8e7e9fbfac6c50157416776
tree: e57ee1003ea6a731483a1a723890ca3c4a866278
  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