mm: ksm: remove unnecessary try_to_freeze()

mm: ksm: remove unnecessary try_to_freeze()

A freezable kernel thread can enter frozen state during freezing by
either calling try_to_freeze() or using wait_event_freezable() and its
variants. However, there is no need to use both methods simultaneously.

Link: https://lkml.kernel.org/r/20231213090906.1070985-1-haokexin@gmail.com
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>