ARM: dts: i.MX51: digi-connectcore-som: Correct Ethernet node name

make dtbs_check:

    lan9221@5,0: $nodename:0: 'lan9221@5,0' does not match '^ethernet(@.*)?$'
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx51-digi-connectcore-som.dtsi

@@ -206,7 +206,7 @@ &weim {
 	pinctrl-0 = <&pinctrl_weim>;
 	status = "okay";
 
-	lan9221: lan9221@5,0 {
+	lan9221: ethernet@5,0 {
 		pinctrl-names = "default";
 		pinctrl-0 = <&pinctrl_lan9221>;
 		compatible = "smsc,lan9221", "smsc,lan9115";