futex/requeue: Remove unnecessary ‘NULL’ initialization from futex_proxy_trylock_atomic()

'top_waiter' is assigned unconditionally before first use,
so it does not need an initialization.

[ mingo: Created legible changelog. ]

Signed-off-by: Li zeming <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

Author: Li zeming

kernel/futex/requeue.c

@@ -269,7 +269,7 @@ futex_proxy_trylock_atomic(u32 __user *pifutex, struct futex_hash_bucket *hb1,
 			   union futex_key *key2, struct futex_pi_state **ps,
 			   struct task_struct **exiting, int set_waiters)
 {
-	struct futex_q *top_waiter = NULL;
+	struct futex_q *top_waiter;
 	u32 curval;
 	int ret;