Update git submodules

* Update ndk from branch 'ndk-release-r19'
  to adf7d097cdafcc6f83453e7f25ba0e6ca5828296
  - Merge "Ensure that stale object files are not used." into ndk-release-r19
  - Ensure that stale object files are not used.
    
    If compilation fails, Clang will remove the output if using the
    integrated assembler, but not when using GAS. The behavior with GAS
    matches GCC's behavior. .DELETE_ON_ERROR does not help because it
    will only clean the output if it changed.
    
    Test: ./checkbuild.py
    Bug: android/ndk#603
    Change-Id: I77c0b5030c49a023f6e674d4a878142b7282ed0e
    (cherry picked from commit 7503fad5572e240a4895f6463cd559bde7479a2d)