cifs: release lock earlier in dequeue_mid error case

In dequeue_mid we can log an error while holding a spinlock,
GlobalMid_Lock.  Coverity notes that the error logging
also grabs a lock so it is cleaner (and a bit safer) to
release the GlobalMid_Lock before logging the warning.

Addresses-Coverity: 1507573 ("Thread deadlock")
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>

fs/cifs/connect.c

@@ -709,13 +709,14 @@ dequeue_mid(struct mid_q_entry *mid, bool malformed)
 	 * Trying to handle/dequeue a mid after the send_recv()
 	 * function has finished processing it is a bug.
 	 */
-	if (mid->mid_flags & MID_DELETED)
+	if (mid->mid_flags & MID_DELETED) {
+		spin_unlock(&GlobalMid_Lock);
 		pr_warn_once("trying to dequeue a deleted mid\n");
-	else {
+	} else {
 		list_del_init(&mid->qhead);
 		mid->mid_flags |= MID_DELETED;
+		spin_unlock(&GlobalMid_Lock);
 	}
-	spin_unlock(&GlobalMid_Lock);
 }
 
 static unsigned int