AudioHal: Do not suspend A2DP on 2nd A2dpSuspended=true request

* Based on existing logic, the second A2dpSuspended=true request will cause
  A2dp to be unsuspended.
* Instead:
  - if A2DP is suspended, A2dpSuspended=true request should be a no-op
  - if A2DP is not suspended, A2dpSuspended=false request should be a
    no-op
  - otherwise, A2dpSuspended request should do what it means to do

Bug: 74988740
Test: Receive incoming call while music is playing
Change-Id: I38fb7e501c7533af3ed3ac989da77d55e5695bc9