[NETFILTER]: annotate xtables targets with const and remove casts

Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
diff --git a/net/netfilter/xt_multiport.c b/net/netfilter/xt_multiport.c
index 31daa81..fd88c48 100644
--- a/net/netfilter/xt_multiport.c
+++ b/net/netfilter/xt_multiport.c
@@ -100,7 +100,8 @@
                 const void *matchinfo, int offset, unsigned int protoff,
                 bool *hotdrop)
 {
-	__be16 _ports[2], *pptr;
+	const __be16 *pptr;
+	__be16 _ports[2];
 	const struct xt_multiport *multiinfo = matchinfo;
 
 	if (offset)
@@ -126,7 +127,8 @@
              const void *matchinfo, int offset, unsigned int protoff,
              bool *hotdrop)
 {
-	__be16 _ports[2], *pptr;
+	const __be16 *pptr;
+	__be16 _ports[2];
 	const struct xt_multiport_v1 *multiinfo = matchinfo;
 
 	if (offset)