Fix typo (double unlock)

Change-Id: If4a128186a732266eb27b6aa3caf6f1feff449bf
Signed-off-by: Dave Barach <dave@barachs.net>
diff --git a/src/vlibmemory/memory_vlib.c b/src/vlibmemory/memory_vlib.c
index 338fda4..7ae7867 100644
--- a/src/vlibmemory/memory_vlib.c
+++ b/src/vlibmemory/memory_vlib.c
@@ -1024,11 +1024,10 @@
 	      if (PREDICT_FALSE (q->head == q->maxsize))
 		q->head = 0;
 	      pthread_mutex_unlock (&q->mutex);
+
 	      if (need_broadcast)
 		(void) pthread_cond_broadcast (&q->condvar);
 
-	      pthread_mutex_unlock (&q->mutex);
-
 	      vl_msg_api_handler_with_vm_node (am, (void *) mp, vm, node);
 	    }
 	  else