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/arm/dts/at91sam9g20ek_common.dtsi b/arch/arm/dts/at91sam9g20ek_common.dtsi
index 7195454..249c88d 100644
--- a/arch/arm/dts/at91sam9g20ek_common.dtsi
+++ b/arch/arm/dts/at91sam9g20ek_common.dtsi
@@ -9,7 +9,7 @@
 
 / {
 	chosen {
-		u-boot,dm-pre-reloc;
+		bootph-all;
 		stdout-path = &dbgu;
 	};
 
@@ -47,7 +47,7 @@
 			};
 
 			dbgu: serial@fffff200 {
-				u-boot,dm-pre-reloc;
+				bootph-all;
 				status = "okay";
 			};