sctp: remove unnecessary byteshifting, calculate directly in big-endian

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sctp/output.c b/net/sctp/output.c
index 9a63a3f..4568464 100644
--- a/net/sctp/output.c
+++ b/net/sctp/output.c
@@ -365,7 +365,7 @@
 	struct sctp_transport *tp = packet->transport;
 	struct sctp_association *asoc = tp->asoc;
 	struct sctphdr *sh;
-	__u32 crc32 = 0;
+	__be32 crc32 = __constant_cpu_to_be32(0);
 	struct sk_buff *nskb;
 	struct sctp_chunk *chunk, *tmp;
 	struct sock *sk;
@@ -538,7 +538,7 @@
 	/* 3) Put the resultant value into the checksum field in the
 	 *    common header, and leave the rest of the bits unchanged.
 	 */
-	sh->checksum = htonl(crc32);
+	sh->checksum = crc32;
 
 	/* IP layer ECN support
 	 * From RFC 2481