[NET]: Annotate checksums in on-the-wire packets.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/icmp.h b/include/linux/icmp.h
index 878cfe4..24da4fb 100644
--- a/include/linux/icmp.h
+++ b/include/linux/icmp.h
@@ -68,7 +68,7 @@
 struct icmphdr {
   __u8		type;
   __u8		code;
-  __be16	checksum;
+  __sum16	checksum;
   union {
 	struct {
 		__be16	id;