Temporarily remove broken SCO-over-HCI implementation

This is currently not used on known Android platforms and currently does
not compile. To be re-visited when SCO-over-HCI can be re-implemented
based on the new HAL.

Test: make
Bug: 70965527
Change-Id: Iefff5b3fb1599a0cdb2c7fb90b463f3643a2a47e