ceph: use fixed endian encoding for ceph_entity_addr

We exchange struct ceph_entity_addr over the wire and store it on disk.
The sockaddr_storage.ss_family field, however, is host endianness.  So,
fix ss_family endianness to big endian when sending/receiving over the
wire.

Signed-off-by: Sage Weil <sage@newdream.net>
diff --git a/fs/ceph/messenger.h b/fs/ceph/messenger.h
index dcd98b6..e016fa7 100644
--- a/fs/ceph/messenger.h
+++ b/fs/ceph/messenger.h
@@ -53,6 +53,7 @@
 
 struct ceph_messenger {
 	struct ceph_entity_inst inst;    /* my name+address */
+	struct ceph_entity_addr my_enc_addr;
 	struct page *zero_page;          /* used in certain error cases */
 
 	bool nocrc;