mm, oom: fix uninitialized ret in task_will_free_mem()

    mm/oom_kill.c: In function `task_will_free_mem':
    mm/oom_kill.c:767: warning: `ret' may be used uninitialized in this function

If __task_will_free_mem() is never called inside the for_each_process()
loop, ret will not be initialized.

Fixes: 1af8bb4 ("mm, oom: fortify task_will_free_mem()")
Link: http://lkml.kernel.org/r/1470255599-24841-1-git-send-email-geert@linux-m68k.org
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/oom_kill.c

@@ -764,7 +764,7 @@ bool task_will_free_mem(struct task_struct *task)
 {
 	struct mm_struct *mm = task->mm;
 	struct task_struct *p;
-	bool ret;
+	bool ret = true;
 
 	/*
 	 * Skip tasks without mm because it might have passed its exit_mm and