sysreset: qemu virt: Use __raw_writel()

The virt ctrl register seems to be native endian, currently this driver
uses writel(), which works by luck because its currently broken on m68k.

Use __raw_writel() instead to avoid breaking this driver when the
endianness of writel() is fixed.

Acked-by: Kuan-Wei Chiu <visitorckw@gmail.com>
Reviewed-by: Angelo Dureghello <angelo@kernel-space.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Daniel Palmer <daniel@thingy.jp>

drivers/sysreset/sysreset_qemu_virt_ctrl.c

@@ -40,7 +40,7 @@ static int qemu_virt_ctrl_request(struct udevice *dev, enum sysreset_t type)
 		return -EPROTONOSUPPORT;
 	}
 
-	writel(val, reg);
+	__raw_writel(val, reg);
 
 	return -EINPROGRESS;
 }