riscv: cpu: jh7110: fallback to generic cleanup_before_linux()

JH7110 SoC requires no specific handling before entering Linux kernel.
Let's drop the specific implementation to avoid duplication.

Signed-off-by: Yao Zi <ziyao@disroot.org>
Reviewed-by: Leo Yu-Chi Liang <ycliang@andestech.com>

arch/riscv/cpu/jh7110/Makefile

@@ -5,6 +5,5 @@
 ifeq ($(CONFIG_XPL_BUILD),y)
 obj-y += spl.o
 else
-obj-y += cpu.o
 obj-y += dram.o
 endif

arch/riscv/cpu/jh7110/cpu.c

@@ -1,23 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0+
-/*
- * Copyright (C) 2022 StarFive Technology Co., Ltd.
- * Author: Yanhong Wang <yanhong.wang@starfivetech.com>
- */
-
-#include <asm/cache.h>
-#include <irq_func.h>
-
-/*
- * cleanup_before_linux() is called just before we call linux
- * it prepares the processor for linux
- *
- * we disable interrupt and caches.
- */
-int cleanup_before_linux(void)
-{
-	disable_interrupts();
-
-	cache_flush();
-
-	return 0;
-}