spl_nor: fix warning when compiled for 64bit target

Fix "warning: cast to pointer from integer of different size".
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: NTom Rini <trini@konsulko.com>

common/spl/spl_nor.c

@@ -59,7 +59,7 @@ int spl_nor_load_image(void)
 	spl_parse_image_header(
 			(const struct image_header *)CONFIG_SYS_UBOOT_BASE);
 
-	memcpy((void *)spl_image.load_addr,
+	memcpy((void *)(unsigned long)spl_image.load_addr,
 	       (void *)(CONFIG_SYS_UBOOT_BASE + sizeof(struct image_header)),
 	       spl_image.size);