riscv: dts: microchip: drop unused pinctrl-names

pinctrl-names without pinctrl-0 does not have any sense:

  arch/riscv/boot/dts/microchip/microchip-mpfs-icicle-kit.dt.yaml: sdhc@20008000: 'pinctrl-0' is a dependency of 'pinctrl-names'

Signed-off-by: Krzysztof Kozlowski <[email protected]>
Reviewed-by: Geert Uytterhoeven <[email protected]>
Signed-off-by: Palmer Dabbelt <[email protected]>

Author: krzk

arch/riscv/boot/dts/microchip/microchip-mpfs.dtsi

@@ -268,7 +268,6 @@
 			reg = <0x0 0x20008000 0x0 0x1000>;
 			interrupt-parent = <&plic>;
 			interrupts = <88 89>;
-			pinctrl-names = "default";
 			clocks = <&clkcfg 6>;
 			max-frequency = <200000000>;
 			status = "disabled";