bnxt: simplify cls_flower command switch and handle default case

Currently the default case is not handled, which with future command
introductions would introduce a warning. So handle it and make the
switch a bit simplier removing unneeded "rc" variable.
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bnxt/bnxt_tc.c

@@ -1544,22 +1544,16 @@ void bnxt_tc_flow_stats_work(struct bnxt *bp)
 int bnxt_tc_setup_flower(struct bnxt *bp, u16 src_fid,
 			 struct tc_cls_flower_offload *cls_flower)
 {
-	int rc = 0;
-
 	switch (cls_flower->command) {
 	case TC_CLSFLOWER_REPLACE:
-		rc = bnxt_tc_add_flow(bp, src_fid, cls_flower);
-		break;
-
+		return bnxt_tc_add_flow(bp, src_fid, cls_flower);
 	case TC_CLSFLOWER_DESTROY:
-		rc = bnxt_tc_del_flow(bp, cls_flower);
-		break;
-
+		return bnxt_tc_del_flow(bp, cls_flower);
 	case TC_CLSFLOWER_STATS:
-		rc = bnxt_tc_get_flow_stats(bp, cls_flower);
-		break;
+		return bnxt_tc_get_flow_stats(bp, cls_flower);
+	default:
+		return -EOPNOTSUPP;
 	}
-	return rc;
 }
 
 static const struct rhashtable_params bnxt_tc_flow_ht_params = {