Bluetooth: ignore state change update from second streaming device

During A2dp playback Ignore state change update from second A2dp device
When there is a connection request from a second a2dp device this change
would avoid wrongly resetting the state of the streaming a2dp device to
improper state.

CRs-Fixed: 414094

Change-Id: I25bc5430ff37603502f4cb6072dbe5476e2baf13