new helper: sigsuspend()

guts of saved_sigmask-based sigsuspend/rt_sigsuspend.  Takes
kernel sigset_t *.

Open-coded instances replaced with calling it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

arch/frv/kernel/signal.c

@@ -40,17 +40,9 @@ struct fdpic_func_descriptor {
  */
 asmlinkage int sys_sigsuspend(int history0, int history1, old_sigset_t mask)
 {
-	mask &= _BLOCKABLE;
-	spin_lock_irq(&current->sighand->siglock);
-	current->saved_sigmask = current->blocked;
-	siginitset(&current->blocked, mask);
-	recalc_sigpending();
-	spin_unlock_irq(&current->sighand->siglock);
-
-	current->state = TASK_INTERRUPTIBLE;
-	schedule();
-	set_thread_flag(TIF_RESTORE_SIGMASK);
-	return -ERESTARTNOHAND;
+	sigset_t blocked;
+	siginitset(&blocked, mask);
+	return sigsuspend(&blocked);
 }
 
 asmlinkage int sys_sigaction(int sig,