Audio V4: Support query microphones information

Get list of all/currently active microphones from hardware.
Part of the device enumeration feature.

Bug: 64038649
Test: test/vts-testcase/hal/script/update_makefiles.py
Change-Id: I08051f1d6013672dea8f3866776864e87ff35297
Rebased for 4.0 by:
Signed-off-by: Kevin Rocard <krocard@google.com>
Originally written by:
Signed-off-by: Ricardo Garcia <rago@google.com>
diff --git a/audio/4.0/IStreamIn.hal b/audio/4.0/IStreamIn.hal
index 3b1fd40..3b2dc25 100644
--- a/audio/4.0/IStreamIn.hal
+++ b/audio/4.0/IStreamIn.hal
@@ -156,4 +156,15 @@
      */
     getCapturePosition()
             generates (Result retval, uint64_t frames, uint64_t time);
+
+    /**
+     * Returns an array with active microphones in the stream.
+     *
+     * @return retval INVALID_STATE if the call is not successful,
+     *                OK otherwise.
+     *
+     * @return microphones array with microphones info
+     */
+    getActiveMicrophones()
+               generates(Result retval, vec<MicrophoneInfo> microphones);
 };