atmel, at91: fix taurus board

since commit: f8b7fff1d5c5 "serial: atmel_usart: Add clk support"

taurus board comes not up anymore. Fix it.

Signed-off-by: Heiko Schocher <hs@denx.de>
Acked-by: Wenyou Yang <wenyou.yang@microchip.com>
diff --git a/arch/arm/dts/at91sam9g20-taurus.dts b/arch/arm/dts/at91sam9g20-taurus.dts
index f27d772..7931c0a 100644
--- a/arch/arm/dts/at91sam9g20-taurus.dts
+++ b/arch/arm/dts/at91sam9g20-taurus.dts
@@ -18,6 +18,7 @@
 	compatible = "atmel,at91sam9g20ek", "atmel,at91sam9g20", "atmel,at91sam9";
 
 	chosen {
+		u-boot,dm-pre-reloc;
 		stdout-path = &dbgu;
 	};
 
@@ -48,6 +49,7 @@
 			};
 
 			dbgu: serial@fffff200 {
+				u-boot,dm-pre-reloc;
 				status = "okay";
 			};