dt: don't use ARCH_CPU_DTS

Now that we assume dtc supports the -i option, we don't need to use
ARCH_CPU_DTS in *.dts{,i}; we simply specify the include filename
directly, and dtc will find it.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/board/chromebook-x86/dts/link.dts b/board/chromebook-x86/dts/link.dts
index d0738cb..c95ee8a 100644
--- a/board/chromebook-x86/dts/link.dts
+++ b/board/chromebook-x86/dts/link.dts
@@ -1,6 +1,6 @@
 /dts-v1/;
 
-/include/ ARCH_CPU_DTS
+/include/ "coreboot.dtsi"
 
 / {
         #address-cells = <1>;