Audio: check and route usecases

Add check_and_route_usecases -

this function is to make sure that all the usecases that are active on
the hardware codec backend are always routed to any one device that is
handled by the hardware codec.

Example:
When voice call starting - we need earpice -
hal enable earpice, but befor - we put call button -
and hal enable speaker and play sound - "click"
And now we have speaker and earpice enabled.
Later when audioflinger send standby (default after 3 sec) to stream
which use speaker - hal disable speaker while voice call active - and
we have no sound in earpice.
check_and_route_usecases will not allow such situations.

Change-Id: Ibc534bb14c25e4a4ffb4f3487d1424e9e1ed6a67