hal: passthru: Fix to avoid mute in DDP passthru

-Mute ovserved on HDMI sink while rendering
high bitrate DDP content
-Offload buffer size is just 2k,
increasing it to handle high bit rate content
-QAF: Session close is blocked if pcm stream open is failed
--This is fixed by cleaning up the pcm stream

Change-Id: Ibc0efd99194ba4039921029f52f580dc9db79503