[NET]: drop duplicate assignment in request_sock

Just noticed that request_sock.[ch] contain a useless assignment of
rskq_accept_head to itself.  I assume this is a typo and the 2nd one
was supposed to be _tail.  However, setting _tail to NULL is not
needed, so the patch below just drops the 2nd assignment.

Signed-off-By: Norbert Kiesel <[email protected]>
Signed-off-by: Adrian Bunk <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
diff --git a/include/net/request_sock.h b/include/net/request_sock.h
index 11641c9..c5d7f92 100644
--- a/include/net/request_sock.h
+++ b/include/net/request_sock.h
@@ -145,7 +145,7 @@
 {
 	struct request_sock *req = queue->rskq_accept_head;
 
-	queue->rskq_accept_head = queue->rskq_accept_head = NULL;
+	queue->rskq_accept_head = NULL;
 	return req;
 }