xtensa: nommu: xtfpga: add kc705 DTS

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

arch/xtensa/boot/dts/kc705_nommu.dts

+/dts-v1/;
+/include/ "xtfpga.dtsi"
+/include/ "xtfpga-flash-128m.dtsi"
+
+/ {
+	compatible = "cdns,xtensa-kc705";
+	chosen {
+		bootargs = "earlycon=uart8250,mmio32,0x9d050020,115200n8 console=ttyS0,115200n8 ip=dhcp root=/dev/nfs rw debug";
+	};
+	memory@0 {
+		device_type = "memory";
+		reg = <0x60000000 0x10000000>;
+	};
+	soc {
+		ranges = <0x00000000 0x90000000 0x10000000>;
+	};
+};