score: make init_thread_union align to THREAD_SIZE

arch/score/kernel/init_task.c

@@ -35,7 +35,7 @@ static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand);
  * "init_task" linker map entry..
  */
 union thread_union init_thread_union
-	__attribute__((__section__(".data.init_task"))) =
+	__attribute__((__section__(".data.init_task"), __aligned__(THREAD_SIZE))) =
 		{ INIT_THREAD_INFO(init_task) };
 
 /*