Revert "net: sctp: convert sctp_checksum_disable module param into sctp sysctl"

This reverts commit cda5f98e36576596b9230483ec52bff3cc97eb21.

As per Vlad's request.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sctp/input.c b/net/sctp/input.c
index 2873e22..5f20686 100644
--- a/net/sctp/input.c
+++ b/net/sctp/input.c
@@ -134,8 +134,8 @@
 	__skb_pull(skb, skb_transport_offset(skb));
 	if (skb->len < sizeof(struct sctphdr))
 		goto discard_it;
-	if (!net->sctp.checksum_disable && !skb_csum_unnecessary(skb) &&
-	    sctp_rcv_checksum(net, skb) < 0)
+	if (!sctp_checksum_disable && !skb_csum_unnecessary(skb) &&
+		  sctp_rcv_checksum(net, skb) < 0)
 		goto discard_it;
 
 	skb_pull(skb, sizeof(struct sctphdr));