dm: dts: Convert driver model tags to use new schema

Now that Linux has accepted these tags, move the device tree files in
U-Boot over to use them.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/x86/dts/reset.dtsi b/arch/x86/dts/reset.dtsi
index f2ba2fb..1f1ff9f 100644
--- a/arch/x86/dts/reset.dtsi
+++ b/arch/x86/dts/reset.dtsi
@@ -1,6 +1,6 @@
 / {
 	reset: reset {
 		compatible = "x86,reset";
-		u-boot,dm-pre-proper;
+		bootph-some-ram;
 	};
 };