net: remove unneeded switch fall-through

This case block has been terminated by a return, so not need
a switch fall-through
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/igmp.c

@@ -1541,7 +1541,6 @@ static int ip_mc_check_igmp_msg(struct sk_buff *skb)
 	case IGMP_HOST_LEAVE_MESSAGE:
 	case IGMP_HOST_MEMBERSHIP_REPORT:
 	case IGMPV2_HOST_MEMBERSHIP_REPORT:
-		/* fall through */
 		return 0;
 	case IGMPV3_HOST_MEMBERSHIP_REPORT:
 		return ip_mc_check_igmp_reportv3(skb);

net/ipv6/mcast_snoop.c

@@ -128,7 +128,6 @@ static int ipv6_mc_check_mld_msg(struct sk_buff *skb)
 	switch (mld->mld_type) {
 	case ICMPV6_MGM_REDUCTION:
 	case ICMPV6_MGM_REPORT:
-		/* fall through */
 		return 0;
 	case ICMPV6_MLD2_REPORT:
 		return ipv6_mc_check_mld_reportv2(skb);