ARM: zynq: Fix bootargs in board dtsi

- Sync with Linux kernel
- Remove rootfs
- Remove earlyprintk

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/arch/arm/dts/zynq-zc770-xm012.dts b/arch/arm/dts/zynq-zc770-xm012.dts
index 8d69f0e..6cab832 100644
--- a/arch/arm/dts/zynq-zc770-xm012.dts
+++ b/arch/arm/dts/zynq-zc770-xm012.dts
@@ -20,7 +20,7 @@
 	};
 
 	chosen {
-		bootargs = "root=/dev/ram rw earlyprintk";
+		bootargs = "";
 		stdout-path = "serial0:115200n8";
 	};