GPIO drivers can be registered quite late in registration process
causing dependant devices to fail probing. If we know gpio_get_num
will be called with a non-NULL device, return -EPROBE_DEFER instead
of -ENODEV to allow re-probing later.
Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>