ceph: hex dump corrupt server data to KERN_DEBUG

Also, print fsid using standard format, NOT hex dump.

Signed-off-by: Sage Weil <sage@newdream.net>
diff --git a/fs/ceph/snap.c b/fs/ceph/snap.c
index 52f46a1..dcf18d9 100644
--- a/fs/ceph/snap.c
+++ b/fs/ceph/snap.c
@@ -877,6 +877,7 @@
 
 bad:
 	pr_err("corrupt snap message from mds%d\n", mds);
+	ceph_msg_dump(msg);
 out:
 	if (locked_rwsem)
 		up_write(&mdsc->snap_rwsem);