x86: dts: Add compatible string for Intel ICH9 SPI controller

Add this to the enum so that we can use the various fdtdec functions. A
later commit will move this driver to driver model.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/include/fdtdec.h b/include/fdtdec.h
index 75af750..8c2bd21 100644
--- a/include/fdtdec.h
+++ b/include/fdtdec.h
@@ -173,6 +173,7 @@
 	COMPAT_INTEL_MODEL_206AX,	/* Intel Model 206AX CPU */
 	COMPAT_INTEL_GMA,		/* Intel Graphics Media Accelerator */
 	COMPAT_AMS_AS3722,		/* AMS AS3722 PMIC */
+	COMPAT_INTEL_ICH_SPI,		/* Intel ICH7/9 SPI controller */
 
 	COMPAT_COUNT,
 };