Fix sync issue in virNetClientStreamEventRemoveCallback

The stream lock is unlocked twice instead of being locked and then
unlocked. Probably a typo.
(cherry picked from commit 107f51b6)

Conflicts:

	AUTHORS

AUTHORS

@@ -233,6 +233,7 @@ Patches have also been contributed by:
   MATSUDA Daiki        <matsudadik@intellilink.co.jp>
   Jan Kiszka           <jan.kiszka@siemens.com>
   Ryan Woodsmall       <rwoodsmall@gmail.com>
+  Radu Caragea         <dmns_serp@yahoo.com>
 
   [....send patches to get your name here....]
 

src/rpc/virnetclientstream.c

@@ -508,7 +508,7 @@ int virNetClientStreamEventRemoveCallback(virNetClientStreamPtr st)
 {
     int ret = -1;
 
-    virMutexUnlock(&st->lock);
+    virMutexLock(&st->lock);
     if (!st->cb) {
         virNetError(VIR_ERR_INTERNAL_ERROR,
                     "%s", _("no stream callback registered"));