gpiolib: remove redundant callback check

The presence of the .get_direction() callback is already checked in
gpiochip_get_direction(). Remove the duplicated check which also returns
the wrong error code to user-space.

Fixes: e623c43 ("gpiolib: sanitize the return value of gpio_chip::get_direction()")
Reported-by: Michael Walle <mwalle@kernel.org>
Closes: https://lore.kernel.org/all/DFJAFK3DTBOZ.3G2P3A5IH34GF@kernel.org/
Link: https://lore.kernel.org/r/20260109105557.20024-1-bartosz.golaszewski@oss.qualcomm.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

Author: Bartosz Golaszewski

drivers/gpio/gpiolib.c

@@ -468,9 +468,6 @@ int gpiod_get_direction(struct gpio_desc *desc)
 	    test_bit(GPIOD_FLAG_IS_OUT, &flags))
 		return 0;
 
-	if (!guard.gc->get_direction)
-		return -ENOTSUPP;
-
 	ret = gpiochip_get_direction(guard.gc, offset);
 	if (ret < 0)
 		return ret;