audio: Allow Stream SM to stay in DRAINING state for early notify

Since for the "early notify" drain the stream sends `onDrainReady`
sligtly before the draining has actually finished, it should be
allowed to stay in the `DRAINING` state while sending this
notification. The stream gets into the `IDLE` state once the drain
has completed. While draining is ongoing, it is allowed for
the client to pause the stream.

As this is a new behavior in audio.core V3, extend VTS to skip
tests that verify this behavior for previous audio HAL versions.

Also, add previously missed `DrainOutAsync` scenario to the tests
list.

Bug: 363958142
Test: atest VtsHalAudioCoreTargetTest
Change-Id: I6878b07c2fa1ce4f19b3c9c5d0e0f2e5288e55c4