Bluetooth: btintel: Define a callback to fetch codec config data

Define callback function to get codec config data. In HFP offload
usecase, controllers need to be set codec details before opening SCO.
This callback function is used to fetch vendor specific codec config
data.

Signed-off-by: Kiran K <kiran.k@intel.com>
Reviewed-by: Chethan T N <chethan.tumkur.narayan@intel.com>
Reviewed-by: Srivatsa Ravishankar <ravishankar.srivatsa@intel.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>