x86: coreboot: Enable support for the configuration editor

Enable cedit support along with required options and a simple style.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/x86/dts/coreboot.dts b/arch/x86/dts/coreboot.dts
index b867468..39d1d32 100644
--- a/arch/x86/dts/coreboot.dts
+++ b/arch/x86/dts/coreboot.dts
@@ -54,6 +54,13 @@
 			menu-inset = <3>;
 			menuitem-gap-y = <1>;
 		};
+
+		cedit-theme {
+			font-size = <30>;
+			menu-inset = <3>;
+			menuitem-gap-y = <1>;
+			menu-title-margin-x = <30>;
+		};
 	};
 
 	sysinfo {