xtensa: xtfpga: fix ethernet controller endianness

Ethernet controller is attached to XTFPGA boards as native endian device,
mark it as such in DTS and pass correct endianness in platform data.
This makes network functional on big-endian CPUs.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

arch/xtensa/boot/dts/xtfpga.dtsi

@@ -69,6 +69,7 @@ serial0: serial@0d050020 {
 		enet0: ethoc@0d030000 {
 			compatible = "opencores,ethoc";
 			reg = <0x0d030000 0x4000 0x0d800000 0x4000>;
+			native-endian;
 			interrupts = <1 1>; /* external irq 1 */
 			local-mac-address = [00 50 c2 13 6f 00];
 			clocks = <&osc>;

arch/xtensa/platforms/xtfpga/setup.c

@@ -223,6 +223,7 @@ static struct ethoc_platform_data ethoc_pdata = {
 	 */
 	.hwaddr = { 0x00, 0x50, 0xc2, 0x13, 0x6f, 0 },
 	.phy_id = -1,
+	.big_endian = XCHAL_HAVE_BE,
 };
 
 static struct platform_device ethoc_device = {