Modem Ring Indicator wake from suspend DT Fragment

This device tree fragment creates a gpio-key interface for the modem Ring Indicator pin that is connected in PinePhone Braveheart and can wake the SoC from s2idle sleep.

gpio_keys {
    compatible = "gpio-keys";
 
    ring_indicator {
        label = "Ring Indicator";
        gpios =  <&pio 1 2 IRQ_TYPE_EDGE_FALLING>; /* PB2 */
        linux,input-type = <EV_KEY>;
        linux,code = <KEY_WAKEUP>;
        linux,can-disable;
        wakeup-source;
    };
};