MAP MCE

Add MAP client code into packages/apps/Bluetooth.  Changes here are to
define the MAP MCE interface and enable its selection when running on a
device that is also running a PBAP client (Car Kitt).

Bug: 30467210
Change-Id: Ifa2cdea7d67f63a2b5f3d971df8ec6d321dc5fee
(cherry picked from commit fae5ff2578fe1e51a4677e6d344d4f5ff4618ed1)