libceph: embed ceph messenger structure in ceph_client

(cherry picked from commit 15d9882c336db2db73ccf9871ae2398e452f694c)

A ceph client has a pointer to a ceph messenger structure in it.
There is always exactly one ceph messenger for a ceph client, so
there is no need to allocate it separate from the ceph client
structure.

Switch the ceph_client structure to embed its ceph_messenger
structure.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/include/linux/ceph/libceph.h b/include/linux/ceph/libceph.h
index e71d683..98ec36a 100644
--- a/include/linux/ceph/libceph.h
+++ b/include/linux/ceph/libceph.h
@@ -132,7 +132,7 @@
 	u32 supported_features;
 	u32 required_features;
 
-	struct ceph_messenger *msgr;   /* messenger instance */
+	struct ceph_messenger msgr;   /* messenger instance */
 	struct ceph_mon_client monc;
 	struct ceph_osd_client osdc;