Merge tag 'android-7.1.0_r4' of https://android.googlesource.com/platform/hardware/qcom/bt into n7.1

Android 7.1.0 release 4
tree: c4a1b71d0372be7dba52a47bcd0173c790c2b2e4
  1. libbt-vendor/
  2. msm8909/
  3. msm8960/
  4. msm8992/
  5. msm8996/
  6. Android.mk