Bluetooth Multi Connect

Allow automotive bluetooth profiles to connect to issue multiple connect
calls without disconnecting other devices.  These client side profiles
either support multiple connections or handle multiple connection
requests gracefully.

Bug: 36789202
Test: Manual, Connect to one paired device then attempt to connect to a
second paired device, observe that HFP and PBAP are both connected on
both devices.

Change-Id: I8bd6aea2b8411ba5585b34292d8c6ec62c5c2f96