Revert "gpio: swnode: don't use the swnode's name as the key for GPIO lookup"

This reverts commit e5d527b.

This software node change doesn't actually fix any current issues
with the kernel, it is an improvement to the lookup process rather
than fixing a live bug. It also causes a couple of regressions with
shipping laptops, which relied on the label based lookup.

There is a fix for the regressions in mainline, the first 5 patches
of [1]. However, those patches are fairly substantial changes and
given the patch causing the regression doesn't actually fix a bug
it seems better to just revert it in stable.

CC: stable@vger.kernel.org # 6.18
Link: https://lore.kernel.org/linux-sound/20251120-reset-gpios-swnodes-v7-0-a100493a0f4b@linaro.org/ [1]
Closes: thesofproject#5599
Closes: thesofproject#5603
Acked-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: charleskeepax

drivers/gpio/gpiolib-swnode.c

@@ -41,7 +41,7 @@ static struct gpio_device *swnode_get_gpio_device(struct fwnode_handle *fwnode)
 	    !strcmp(gdev_node->name, GPIOLIB_SWNODE_UNDEFINED_NAME))
 		return ERR_PTR(-ENOENT);
 
-	gdev = gpio_device_find_by_fwnode(fwnode);
+	gdev = gpio_device_find_by_label(gdev_node->name);
 	return gdev ?: ERR_PTR(-EPROBE_DEFER);
 }