alarmtimer: Access timerqueue node under lock in suspend

alarmtimer: Access timerqueue node under lock in suspend

In alarmtimer_suspend(), timerqueue_getnext() is called under
base->lock, but next->expires is read after the lock is released.

This is safe because suspend freezes all relevant task contexts,
but reading the node while holding the lock makes the code easier
to reason about and not worry about a theoretical UAF.

Signed-off-by: Zhan Xusheng <zhanxusheng@xiaomi.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260407143627.19405-1-zhanxusheng@xiaomi.com