audio policy: fix remote submix capture concurrency

Capture from REMOTE_SUBMIX audio source should always be
allowed in concurrency situation.

Also include FM_TUNER as virtual source that should never be
silenced.

Also remove voice call capture sources from privacy senitive sources
as capturing a voice call does not constitute in itself a situation
that should prevent other apps from accessing the mic.

Bug: 121200677
Test: verify music playback in auto projected mode.
Change-Id: Idbd9e9f55f29fb8a8e2b76cea5b85f0d9a555788