ARM: dts: imx6qdl: remove redundant usbmisc label

There is a redundant label on usbmisc node.  Remove it.
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>

arch/arm/boot/dts/imx6qdl.dtsi

@@ -640,7 +640,7 @@
 				status = "disabled";
 			};
 
-			usbmisc: usbmisc: usbmisc@02184800 {
+			usbmisc: usbmisc@02184800 {
 				#index-cells = <1>;
 				compatible = "fsl,imx6q-usbmisc";
 				reg = <0x02184800 0x200>;