watchdog: gpio_wdt: add ACPI support

watchdog: gpio_wdt: add ACPI support

The gpio_wdt device driver uses the device property APIs, so it is
firmware agnostic. For this reason we can now add the ACPI support in
Kconfig.
In this way it can be used seamlessly in ACPI and DT systems.

For example, a typical GPIO watchdog device configuration, in an ACPI
SSDT table, could be:

Device (WDOG) {
    Name (_HID, "WDOG0001")
    Name (_CID, "PRP0001")
    Name (_UID, One)
    Name (_CRS, ResourceTemplate () {
        GpioIo (Exclusive, PullNone, 0, 0, IoRestrictionOutputOnly,
                "\\_SB.GPI0", 0, ResourceConsumer, ,) { 3 }
    })
    Method (_STA, 0, NotSerialized) {
        Return (0x0F)
    }
    Name (_DSD, Package (2)
    {
        ToUUID ("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
        Package (5)
        {
            Package () { "compatible", Package() { "linux,wdt-gpio" } },
            Package () { "hw_algo", "toggle" },
            Package () { "gpios", Package () { ^WDOG, 0, 0, 0 } },
            Package () { "hw_margin_ms", 2000 },
            Package () { "always-running", 1 },
        },
    })
}

Signed-off-by: Flavio Suligoi <f.suligoi@asem.it>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20260323125204.164785-2-f.suligoi@asem.it
Signed-off-by: Guenter Roeck <linux@roeck-us.net>