ARM: dts: rk312x: pinctrl pullup UART1 RX pin

UART RX pin need pullup to keep high voltage when bus is idle.

Change-Id: Iaeea6535bfc42d3ffec396798778cf8803cf3e90
Signed-off-by: Liang Chen <cl@rock-chips.com>

Author: Liang Chen

arch/arm/boot/dts/rk312x.dtsi

@@ -1144,7 +1144,7 @@
 		uart1 {
 			uart1_xfer: uart1-xfer {
 				rockchip,pins = <1 RK_PB1 2 &pcfg_pull_default>,
-						<1 RK_PB2 2 &pcfg_pull_none>;
+						<1 RK_PB2 2 &pcfg_pull_default>;
 			};
 
 			uart1_cts: uart1-cts {