arm64: dts: mediatek: mt8173: Enable cros-ec-spi as wake source

The cros_ec driver currently assumes that cros-ec-spi compatible device
nodes are a wakeup-source even though the wakeup-source property is not
defined.

Some Chromebooks use a separate wake pin, while others overload the
interrupt for wake and IO. With the current assumption, spurious wakes
can occur on systems that use a separate wake pin. It is planned to
update the driver to no longer assume that the EC interrupt pin should
be enabled for wake.

Add the wakeup-source property to all cros-ec-spi compatible device
nodes to signify to the driver that they should still be a valid wakeup
source.
Signed-off-by: Mark Hasemeyer <markhas@chromium.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20240102140734.v4.9.Ic09ebe116c18e83cc1161f4bb073fea8043f03f3@changeidSigned-off-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>

arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi

@@ -1155,6 +1155,7 @@ cros_ec: ec@0 {
 		spi-max-frequency = <12000000>;
 		interrupts-extended = <&pio 0 IRQ_TYPE_LEVEL_LOW>;
 		google,cros-ec-spi-msg-delay = <500>;
+		wakeup-source;
 
 		i2c_tunnel: i2c-tunnel0 {
 			compatible = "google,cros-ec-i2c-tunnel";