Add fast flag under primary 

Fix AUDIO_OUTPUT_FLAG_FAST denied by client due to mismatching sample rate (48000 vs 44100) logcat spam.
Change-Id: I1f1146392855e9e886ae0c2b07d9441ded55ddd4
Signed-off-by: dr87 <nb00870@gmail.com>
https://github.com/SlimRoms/device_lge_g2-common/commit/bc945fb68df14ba72a92b1ea189221d088d77213