Remove ndk_platform backend. Use the ndk backend. am: 547a1a4e1f

Original change: https://android-review.googlesource.com/c/platform/system/libfmq/+/1867815

Change-Id: Ic403e95e491c572bf2ce1cde8b55f2259624bf2a
tree: 54272e31b0b888a0b6cfb1f0b591c2462a51546c
  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