PBAP: Add support for PBAP 1.2

Add changes required to do the SDP registration as
supported by 1.2, L2CAP related functionality and counter
related changes to support PBAP 1.2.

Test: Connected with Remote PBAP Client supporting PBAP 1.2 and
      verified that connection and transfer happens over L2CAP.
      Connected with Remote PBAP Client supporting PBAP 1.1 and
      and verified that connection and transfer happens over RFCOMM.
      TestTracker: 89053 

Bug: 33011817
Change-Id: Iddace24f43a7618ccbe6a9b49bcab88dbaae0e06
(cherry picked from commit 5a37bc40)