rockchip: allow to build SPI images even without HAS_ROM option

This prepares for the creation of a u-boot-rockchip-spi.bin image
similar to u-boot-rockchip.bin to the exception it's destined for
SPI-NOR flashes instead of MMC storage medium.

Cc: Quentin Schulz <foss+uboot@0leil.net>
Signed-off-by: Quentin Schulz <quentin.schulz@theobroma-systems.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/arch/arm/dts/rk3399-u-boot.dtsi b/arch/arm/dts/rk3399-u-boot.dtsi
index 716b9a4..3c1a15f 100644
--- a/arch/arm/dts/rk3399-u-boot.dtsi
+++ b/arch/arm/dts/rk3399-u-boot.dtsi
@@ -60,7 +60,7 @@
 
 };
 
-#ifdef CONFIG_ROCKCHIP_SPI_IMAGE
+#if defined(CONFIG_ROCKCHIP_SPI_IMAGE) && defined(CONFIG_HAS_ROM)
 &binman {
 	rom {
 		filename = "u-boot.rom";