ARM: dts: rockchip: remove pinctrl setting from radxarock uart2

We set default pinctrl settings for the uarts in rk3188.dtsi already,
so remove forgotten duplicate.
Signed-off-by: NHeiko Stuebner <heiko@sntech.de>

arch/arm/boot/dts/rk3188-radxarock.dts

@@ -215,8 +215,6 @@
 };
 
 &uart2 {
-	pinctrl-names = "default";
-	pinctrl-0 = <&uart2_xfer>;
 	status = "okay";
 };