dts: add support for uart1 usage on imx8ml_m7 devicetree include file

Add support for UART1 usage by adding uart1 node and configuration
to the i.MX 8ML devicetree include.

Signed-off-by: Gabriel Freitas <gabriel.freitas@toradex.com>

dts/arm/nxp/nxp_imx8ml_m7.dtsi

@@ -155,10 +155,6 @@
 			status = "disabled";
 		};
 
-		/*
-		 * For now only UART4 is supported and
-		 * tested with the serial driver
-		 */
 		uart4: uart@30a60000 {
 			compatible = "nxp,imx-iuart";
 			reg = <0x30a60000 0x10000>;
@@ -167,6 +163,14 @@
 			status = "disabled";
 		};
 
+		uart1: uart@30860000 {
+            compatible = "nxp,imx-iuart";
+            reg = <0x30860000 0x10000>;
+            interrupts = <26 3>;
+            clocks = <&ccm IMX_CCM_UART1_CLK 0x7c 24>;
+            status = "disabled";
+        };
+
 		mailbox0: mailbox@30ab0000 {
 			compatible = "nxp,imx-mu";
 			reg = <0x30ab0000 DT_SIZE_K(64)>;