ceph: save peer feature bits in connection structure

These are used for adjusting behavior, such as conditionally encoding a
newer message format.
Signed-off-by: Sage Weil <sage@newdream.net>

fs/ceph/messenger.c

@@ -1223,6 +1223,7 @@ static int process_connect(struct ceph_connection *con)
 		clear_bit(CONNECTING, &con->state);
 		con->peer_global_seq = le32_to_cpu(con->in_reply.global_seq);
 		con->connect_seq++;
+		con->peer_features = server_feat;
 		dout("process_connect got READY gseq %d cseq %d (%d)\n",
 		     con->peer_global_seq,
 		     le32_to_cpu(con->in_reply.connect_seq),

fs/ceph/messenger.h

@@ -142,6 +142,7 @@ struct ceph_connection {
 	struct ceph_entity_addr peer_addr; /* peer address */
 	struct ceph_entity_name peer_name; /* peer name */
 	struct ceph_entity_addr peer_addr_for_me;
+	unsigned peer_features;
 	u32 connect_seq;      /* identify the most recent connection
 				 attempt for this connection, client */
 	u32 peer_global_seq;  /* peer's global seq for this connection */