Eliminate a warning about an uninitilized variable

fs/mqueue/mq_open.c

@@ -108,13 +108,13 @@
  *        messages that may be placed in the message queue.
  *
  * Return Value:
- *   A message queue descriptor or -1 (ERROR)
+ *   A message queue descriptor or (mqd_t)-1 (ERROR)
  *
  * Assumptions:
  *
  ****************************************************************************/
 
-mqd_t mq_open(const char *mq_name, int oflags, ...)
+mqd_t mq_open(FAR const char *mq_name, int oflags, ...)
 {
   FAR struct inode *inode;
   FAR const char *relpath = NULL;
@@ -129,20 +129,24 @@ mqd_t mq_open(const char *mq_name, int oflags, ...)
 
   /* Make sure that a non-NULL name is supplied */
 
-  if (mq_name)
+  if (!mq_name)
     {
-      /* Make sure that the check for the existence of the message queue
+      errcode = EINVAL;
-       * and the creation of the message queue are atomic with respect to
+      goto errout;
-       * other processes executing mq_open().  A simple sched_lock() should
+    }
-       * be sufficientt.
-       */
-
-      sched_lock();
 
   /* Get the full path to the message queue */
 
   snprintf(fullpath, MAX_MQUEUE_PATH, CONFIG_FS_MQUEUE_MPATH "/%s", mq_name);
 
+  /* Make sure that the check for the existence of the message queue
+   * and the creation of the message queue are atomic with respect to
+   * other processes executing mq_open().  A simple sched_lock() should
+   * be sufficient.
+   */
+
+  sched_lock();
+
   /* Get the inode for this mqueue.  This should succeed if the message
    * queue has already been created.
    */
@@ -234,11 +238,10 @@ mqd_t mq_open(const char *mq_name, int oflags, ...)
       INODE_SET_MQUEUE(inode);
       inode->u.i_mqueue = msgq;
       msgq->inode       = inode;
+
     }
 
   sched_unlock();
-    }
-
   return mqdes;
 
 errout_with_msgq:
@@ -248,6 +251,7 @@ errout_with_inode:
   inode_release(inode);
 errout_with_lock:
   sched_unlock();
+errout:
   set_errno(errcode);
   return (mqd_t)ERROR;
 }