rockchip: rk3288: revise CONFIG_FASTBOOT_BUF_ADDR

CONFIG_SYS_LOAD_ADDR is absolutely safe to store image for
fastboot.

Signed-off-by: Ziyuan Xu <xzy.xu@rock-chips.com>
Acked-by: Simon Glass <sjg@chromium.org>

include/configs/rk3288_common.h

@@ -93,9 +93,7 @@
 #define CONFIG_USB_FUNCTION_FASTBOOT
 #define CONFIG_FASTBOOT_FLASH
 #define CONFIG_FASTBOOT_FLASH_MMC_DEV	1	/* eMMC */
-/* stroe safely fastboot buffer data to the middle of bank */
-#define CONFIG_FASTBOOT_BUF_ADDR	(CONFIG_SYS_SDRAM_BASE \
-					+ SDRAM_BANK_SIZE / 2)
+#define CONFIG_FASTBOOT_BUF_ADDR	CONFIG_SYS_LOAD_ADDR
 #define CONFIG_FASTBOOT_BUF_SIZE	0x08000000
 
 #define CONFIG_USB_GADGET_DOWNLOAD