ARM: dts: zynq: correct and improve the model property of dt files

Replace the current value of the model property by a more accurate
description of each board (which includes the manufacturer), as some
of the boards had the same value ("Xilinx Zynq")

Signed-off-by: Luis Araneda <luaraneda@gmail.com>
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 19d5b27..0d001c9 100644
--- a/arch/arm/dts/zynq-zc770-xm012.dts
+++ b/arch/arm/dts/zynq-zc770-xm012.dts
@@ -8,8 +8,8 @@
 #include "zynq-7000.dtsi"
 
 / {
+	model = "Xilinx ZC770 XM012 board";
 	compatible = "xlnx,zynq-zc770-xm012", "xlnx,zynq-7000";
-	model = "Xilinx Zynq";
 
 	aliases {
 		i2c0 = &i2c0;