android/gatt: Add helper for getting device by conn_id
android/gatt: Add helper for getting device by conn_id

It will look for cgatt_device by conn_id.

ComputeCycles/bluez,mapfau/bluez,silent-snowman/bluez,pstglia/external-bluetooth-bluez,mapfau/bluez,pstglia/external-bluetooth-bluez,ComputeCycles/bluez,pkarasev3/bluez,mapfau/bluez,silent-snowman/bluez,pstglia/external-bluetooth-bluez,pkarasev3/bluez,pkarasev3/bluez,mapfau/bluez,pstglia/external-bluetooth-bluez,ComputeCycles/bluez,ComputeCycles/bluez,silent-snowman/bluez,pkarasev3/bluez,silent-snowman/bluez