Add faceauth HAL APEX

This moves the faceauth HAL into a vendor apex:
  com.android.hardware.biometrics.face

The contents:

  ./apex_manifest.pb
  ./bin/hw/android.hardware.biometrics.face-service.example
  ./etc/face-default-apex.rc
  ./etc/permissions/android.hardware.biometrics.face.prebuilt.xml
  ./etc/vintf/face-default-apex.xml
  ./lib64/android.hardware.biometrics.common-V2-ndk.so
  ./lib64/android.hardware.biometrics.face-V2-ndk.so
  ./lib64/android.hardware.keymaster-V3-ndk.so

Bug: 279674662
Test: Not installed yet
Test: m com.android.hardware.biometrics.face
Change-Id: I6e52c83601d29bcc6a9ef4e165fab48f3579426c