ARM: dts: aspeed: wedge40: Update UART4 pin settings

Enable UART4's NRTS4 (A19) pin because the pin is used for RS485
software emulation.
Signed-off-by: Tao Ren <rentao.bupt@gmail.com>
Link: https://lore.kernel.org/r/20200824182955.7988-3-rentao.bupt@gmail.comSigned-off-by: Joel Stanley <joel@jms.id.au>

arch/arm/boot/dts/aspeed-bmc-facebook-wedge40.dts

@@ -71,7 +71,8 @@ &uart4 {
 	status = "okay";
 	pinctrl-names = "default";
 	pinctrl-0 = <&pinctrl_txd4_default
-		     &pinctrl_rxd4_default>;
+		     &pinctrl_rxd4_default
+		     &pinctrl_ndts4_default>;
 };
 
 &uart5 {