Bluetooth: PBAP: Add support for PBAP UI preference

This pach adds support for PBAP UI preference in SettingsLib. Without this
change it is not possible to properly use the pbap checkbox preference from
Bluetooth subsettings menu. Also some map profile specific bug fixes are also
incorporated in this change.

Change-Id: I283a0cb65cb132931010fb2f8c977bea20a67951
CRs-Fixed: 758697