sched: clean up sched_getaffinity()

here's another tiny cleanup.  The generated code is not affected (gcc is
smart enough) but for people looking over the code it is just irritating
to have the extra conditional.

Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/sched.c

@@ -4473,10 +4473,8 @@ long sched_getaffinity(pid_t pid, cpumask_t *mask)
 out_unlock:
 	read_unlock(&tasklist_lock);
 	mutex_unlock(&sched_hotcpu_mutex);
-	if (retval)
-		return retval;
 
-	return 0;
+	return retval;
 }
 
 /**