[NETFILTER]: Parenthesize macro parameters

Parenthesize macro parameters.

Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c
index bb50d0e..4ed16d2 100644
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -102,7 +102,7 @@
 	unsigned long ret;
 	const struct ipv6hdr *ipv6 = ipv6_hdr(skb);
 
-#define FWINV(bool,invflg) ((bool) ^ !!(ip6info->invflags & invflg))
+#define FWINV(bool, invflg) ((bool) ^ !!(ip6info->invflags & (invflg)))
 
 	if (FWINV(ipv6_masked_addr_cmp(&ipv6->saddr, &ip6info->smsk,
 				       &ip6info->src), IP6T_INV_SRCIP)