arm64: dts: imx8ulp: correct the scmi sram node name

Follow sram/sram.yaml to update the sram node name.
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8ulp.dtsi

@@ -112,7 +112,7 @@ sram@2201f000 {
 		#size-cells = <1>;
 		ranges = <0 0x0 0x2201f000 0x1000>;
 
-		scmi_buf: scmi-buf@0 {
+		scmi_buf: scmi-sram-section@0 {
 			compatible = "arm,scmi-shmem";
 			reg = <0x0 0x400>;
 		};