Bluetooth: Rename ctrl_id to remote_amp_id

Since we have started to use local_amp_id for local AMP
Controller Id it makes sense to rename ctrl_id to remote_amp_id
since it represents remote AMP controller Id.

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>