audio hal: mmap capture mute

Implement in_set_gain() input stream method for mmap capture
use case only in order to enable silencing the memory mapped
capture buffer at the source.

Bug: 72134552
Test: manual
Change-Id: Ifda75ebb47b31cc2f35e7b68761dcc11f084282b
1 file changed
tree: ddddd0ed11c8de675cba03e8407f9fe0f0a20a65
  1. hal/
  2. legacy/
  3. post_proc/
  4. visualizer/
  5. voice_processing/
  6. Android.mk