Fix system/libfmq compiling against musl am: 02ec6a2f43

Original change: https://android-review.googlesource.com/c/platform/system/libfmq/+/1826813

Change-Id: I2e483b7c619153b8b244b43fd61b8842cd262a47
tree: b881890651c645b5ef3fde32a1ff9eb83684a7fe
  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