netfilter: xtables: change hotdrop pointer to direct modification

Since xt_action_param is writable, let's use it. The pointer to
'bool hotdrop' always worried (8 bytes (64-bit) to write 1 byte!).
Surprisingly results in a reduction in size:

   text    data     bss filename
5457066  692730  357892 vmlinux.o-prev
5456554  692730  357892 vmlinux.o

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
diff --git a/net/netfilter/xt_sctp.c b/net/netfilter/xt_sctp.c
index 94d8b5deb..c04fcf3 100644
--- a/net/netfilter/xt_sctp.c
+++ b/net/netfilter/xt_sctp.c
@@ -128,7 +128,7 @@
 	sh = skb_header_pointer(skb, par->thoff, sizeof(_sh), &_sh);
 	if (sh == NULL) {
 		pr_debug("Dropping evil TCP offset=0 tinygram.\n");
-		*par->hotdrop = true;
+		par->hotdrop = true;
 		return false;
 	}
 	pr_debug("spt: %d\tdpt: %d\n", ntohs(sh->source), ntohs(sh->dest));
@@ -140,7 +140,7 @@
 			&& ntohs(sh->dest) <= info->dpts[1],
 			XT_SCTP_DEST_PORTS, info->flags, info->invflags)
 		&& SCCHECK(match_packet(skb, par->thoff + sizeof(sctp_sctphdr_t),
-					info, par->hotdrop),
+					info, &par->hotdrop),
 			   XT_SCTP_CHUNK_TYPES, info->flags, info->invflags);
 }