x86: qemu: Mark ucode as optional for SPL in u-boot.dtsi

QEMU does not need ucode and this is indicated in u-boot.dtsi
for U-Boot proper. Now add the same for SPL.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

arch/x86/dts/emulation-u-boot.dtsi

@@ -10,9 +10,15 @@
 #ifdef CONFIG_ROM_SIZE
 / {
 	binman {
+#ifdef CONFIG_SPL
+		u-boot-spl-with-ucode-ptr {
+			optional-ucode;
+		};
+#else
 		u-boot-with-ucode-ptr {
 			optional-ucode;
 		};
+#endif
 	};
 };
 #endif