arm64: dts: qcom: sm8250: Rename UART2 node to UART12

The UART12 node has been mistakenly mentioned as UART2. Let's fix that
for both SM8250 SoC and MTP board and also add pinctrl definition for
it.

Fixes: 60378f1a ("arm64: dts: qcom: sm8250: Add sm8250 dts file")
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20200904063637.28632-3-manivannan.sadhasivam@linaro.orgSigned-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

arch/arm64/boot/dts/qcom/sm8250-mtp.dts

@@ -17,7 +17,7 @@ / {
 	compatible = "qcom,sm8250-mtp";
 
 	aliases {
-		serial0 = &uart2;
+		serial0 = &uart12;
 	};
 
 	chosen {
@@ -371,7 +371,7 @@ &tlmm {
 	gpio-reserved-ranges = <28 4>, <40 4>;
 };
 
-&uart2 {
+&uart12 {
 	status = "okay";
 };
 

arch/arm64/boot/dts/qcom/sm8250.dtsi

@@ -936,11 +936,13 @@ spi12: spi@a90000 {
 				status = "disabled";
 			};
 
-			uart2: serial@a90000 {
+			uart12: serial@a90000 {
 				compatible = "qcom,geni-debug-uart";
 				reg = <0x0 0x00a90000 0x0 0x4000>;
 				clock-names = "se";
 				clocks = <&gcc GCC_QUPV3_WRAP1_S4_CLK>;
+				pinctrl-names = "default";
+				pinctrl-0 = <&qup_uart12_default>;
 				interrupts = <GIC_SPI 357 IRQ_TYPE_LEVEL_HIGH>;
 				status = "disabled";
 			};
@@ -1881,6 +1883,13 @@ config {
 					bias-disable;
 				};
 			};
+
+			qup_uart12_default: qup-uart12-default {
+				mux {
+					pins = "gpio34", "gpio35";
+					function = "qup12";
+				};
+			};
 		};
 
 		adsp: remoteproc@17300000 {