libceph: make ceph_msgr_wq private

The messenger workqueue has no need to be public.  So give it static
scope.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>

include/linux/ceph/messenger.h

@@ -14,8 +14,6 @@
 struct ceph_msg;
 struct ceph_connection;
 
-extern struct workqueue_struct *ceph_msgr_wq;       /* receive work queue */
-
 /*
  * Ceph defines these callbacks for handling connection events.
  */

net/ceph/messenger.c

@@ -97,7 +97,7 @@ static void encode_my_addr(struct ceph_messenger *msgr)
 /*
  * work queue for all reading and writing to/from the socket.
  */
-struct workqueue_struct *ceph_msgr_wq;
+static struct workqueue_struct *ceph_msgr_wq;
 
 int ceph_msgr_init(void)
 {