gpio is deprecated. Found with dtc's -Wdeprecated_gpio_property
Used git grep -E $'\tgpio = <' to make the changes.
Signed-off-by: Rosen Penev <rosenp@gmail.com>
Link: https://github.com/openwrt/openwrt/pull/15681
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>