gsm->num is the index of gsm_mux[], it's invalid before calling gsm_activate_mux.
Signed-off-by: Nxinhui.pan <xinhuiX.pan@intel.com>
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>