Do not try to perform feature/capability specific actions if we're still
unlocked, as the modem didn't yet export the feature/capability specific
interface.
The only interfaces expected while modem is unlocked are the Modem and Simple
interfaces, as well as the SIM interface in the SIM object, of course.
Renamed `MMCommonLocation3gpp' to `MMLocation3gpp', and removed the
`MMModemLocation3gpp' provided in libmm-glib. We'll just use the original one
from libmm-common always.
