[IPV4]: ICMP header annotations

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/icmp.h

@@ -68,16 +68,16 @@
 struct icmphdr {
   __u8		type;
   __u8		code;
-  __u16		checksum;
+  __be16	checksum;
   union {
 	struct {
-		__u16	id;
-		__u16	sequence;
+		__be16	id;
+		__be16	sequence;
 	} echo;
-	__u32	gateway;
+	__be32	gateway;
 	struct {
-		__u16	__unused;
-		__u16	mtu;
+		__be16	__unused;
+		__be16	mtu;
 	} frag;
   } un;
 };