Bluetooth: Add PBAP profile and basic server implementation

Add PBAP profile service and implement basic PBAP server implementation
including connect/disconnect.

BUG=b:424465503
TEST=Manually verify PBAP service using sdptool and PBAP client

Change-Id: I4fceecf05f522ac2bd1f5e57648fc4b471a46013
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/chameleon/+/7075722
Commit-Queue: Manish Mandlik <mmandlik@chromium.org>
Reviewed-by: John Lai <johnlai@google.com>
Tested-by: Manish Mandlik <mmandlik@chromium.org>