* Samsung eMMC reset

Some exynos boards require special handling of nRESET_OUT line for eMMC memory
to perform complete reboot.

Required properties:
- compatible: should be "samsung,emmc-reset"
- reset-gpio: gpio chip for eMMC reset.

Example:

emmc-reset {
        compatible = "samsung,emmc-reset";
        reset-gpio = <&gpk1 2 0>;
};