arm64: dts: imx8mm: Drop xtal clock specifier from eDM SBC

The clk_xtal32k have clock-cells = <0>, drop the bogus specifier.

Fixes: 9509593f ("arm64: dts: imx8mm: Model PMIC to SNVS RTC clock path on Data Modul i.MX8M Mini eDM SBC")
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8mm-data-modul-edm-sbc.dts

@@ -275,7 +275,7 @@ pmic: pmic@4b {
 		compatible = "rohm,bd71847";
 		reg = <0x4b>;
 		#clock-cells = <0>;
-		clocks = <&clk_xtal32k 0>;
+		clocks = <&clk_xtal32k>;
 		clock-output-names = "clk-32k-out";
 		pinctrl-names = "default";
 		pinctrl-0 = <&pinctrl_pmic>;