msm: audio: qdsp6v2: Handle subsystem restart on priority in voice driver

Problem Description:
When subsystem restart occurs, voice driver has to clean up
its own handles, so upcoming session handles are maintained.

Impact:
After multiple iterations of subsystem restart occuring, voice
functionality and/or audio functionality may fail.

Solution:
When subsystem restart occurs, apr driver informs voice driver about
the event; Voice driver has to clean up its own handles. This has to
be done on priority. The voice_get_session can be handled after
checking for this event. If it is RESET event, handle that first
so cleaning up the handles are not missed during this high priority
task

Change-Id: I0dc23c2427b7f6fd0ab91f865c3113fa69bba7fc
Signed-off-by: Swaminathan Sathappan <Swami@codeaurora.org>