iwlwifi: mvm: rs: fix a warning message

WARN_ON_ONCE() doesn't take a message, it only takes a condition.  I
have changed this to WARN(1, ...).
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

drivers/net/wireless/intel/iwlwifi/mvm/rs.c

@@ -1827,7 +1827,7 @@ static int rs_switch_to_column(struct iwl_mvm *mvm,
 		rate->type = lq_sta->is_vht ? LQ_VHT_MIMO2 : LQ_HT_MIMO2;
 		rate_mask = lq_sta->active_mimo2_rate;
 	} else {
-		WARN_ON_ONCE("Bad column mode");
+		WARN_ONCE(1, "Bad column mode");
 	}
 
 	if (column->mode != RS_LEGACY) {