audio: add flag for the Ultrasound input source and content_type

Adding the AUDIO_OUTPUT_FLAG_ULTRASOUND and AUDIO_INPUT_FLAG_ULTRASOUND
for the Ultrasound playback and capture respectively.

Note: This upstreaming patch only adds necessary enums.

Bug: 200256985
Test: build pass
Signed-off-by: Carter Hsu <carterhsu@google.com>
Change-Id: I2b56b8ef72fbeed50f960fd41e6b992dbb4f8daa
Merged-In: I2b56b8ef72fbeed50f960fd41e6b992dbb4f8daa