Force the alignment of the chars arrays, as they are casted later to

structs.
gcc 4.2 doesn't do it by default, and that results in unaligned access on
arm.

Reviewed by:	gnn, imp

sys/netinet6/nd6.c

@@ -2309,7 +2309,7 @@ static int
 nd6_sysctl_drlist(SYSCTL_HANDLER_ARGS)
 {
 	int error;
-	char buf[1024];
+	char buf[1024] __aligned(4);
 	struct in6_defrouter *d, *de;
 	struct nd_defrouter *dr;
 
@@ -2347,7 +2347,7 @@ static int
 nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS)
 {
 	int error;
-	char buf[1024];
+	char buf[1024] __aligned(4);
 	struct in6_prefix *p, *pe;
 	struct nd_prefix *pr;
 	char ip6buf[INET6_ADDRSTRLEN];