signal: make flush_sigqueue_mask() void

The return value of flush_sigqueue_mask() is never checked anywhere.

Link: http://lkml.kernel.org/r/20180602103653.18181-14-christian@brauner.io
Signed-off-by: Christian Brauner <christian@brauner.io>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: James Morris <james.morris@microsoft.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/signal.c

@@ -687,14 +687,14 @@ void signal_wake_up_state(struct task_struct *t, unsigned int state)
  *
  * All callers must be holding the siglock.
  */
-static int flush_sigqueue_mask(sigset_t *mask, struct sigpending *s)
+static void flush_sigqueue_mask(sigset_t *mask, struct sigpending *s)
 {
 	struct sigqueue *q, *n;
 	sigset_t m;
 
 	sigandsets(&m, mask, &s->signal);
 	if (sigisemptyset(&m))
-		return 0;
+		return;
 
 	sigandnsets(&s->signal, &s->signal, mask);
 	list_for_each_entry_safe(q, n, &s->list, list) {
@@ -703,7 +703,6 @@ static int flush_sigqueue_mask(sigset_t *mask, struct sigpending *s)
 			__sigqueue_free(q);
 		}
 	}
-	return 1;
 }
 
 static inline int is_si_special(const struct siginfo *info)