Add A2DP src and sink co-exist feature stack layer (3/5)

[Description]
Add A2DP src and sink co-exist feature, that we can connect
both sink and src remote device at the same time while only
keep 1 streaming.

Bug: 256938279
Test: A2DP src/sink connect, streaming successully,
net_test_btif_rc unit test pass

Change-Id: I89ee7391253daffa8992a5e1fafba38635414641