arm64: dts: imx8mp-msc-sm2s-ep1: Remove invalid sgtl5000 property

As per sgtl5000.yaml, 'clock-names' is not a valid property.

Remove it to fix the following schema warning:

imx8mp-msc-sm2s-ep1.dtb: audio-codec@a: Unevaluated properties are not allowed ('clock-names' was unexpected)
Signed-off-by: Fabio Estevam <festevam@denx.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8mp-msc-sm2s-ep1.dts

@@ -55,7 +55,6 @@ sgtl5000: audio-codec@a {
 		assigned-clock-parents = <&clk IMX8MP_CLK_24M>;
 		assigned-clock-rates = <24000000>;
 		clocks = <&clk IMX8MP_CLK_CLKOUT1>;
-		clock-names = "mclk";
 		#sound-dai-cells = <0>;
 
 		VDDA-supply  = <&reg_vcc_3v3_audio>;