iwlwifi: mvm: notify scan completed even if no fw_restart

Notify scan completed if fw_restart flow isn't going to be run.
Otherwise, the scan will stay stack forever and mac80211 will
not be able to remove the interface.

Signed-off-by: David Spinadel <david.spinadel@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>