gpiolib: clear requested flag if line is invalid

If `gpiochip_line_is_valid()` fails, then `-EINVAL` is returned, but
`desc->flags` will have `GPIOD_FLAG_REQUESTED` set, which will result
in subsequent calls misleadingly returning `-EBUSY`.

Fix that by clearing the flag in case of failure.

Fixes: a501624 ("gpio: Respect valid_mask when requesting GPIOs")
Signed-off-by: Barnabás Pőcze <pobrn@protonmail.com>
Reviewed-by: Matti Vaittinen <mazziesaccount@gmail.com>
Link: https://patch.msgid.link/20260310204359.1202451-1-pobrn@protonmail.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

Author: pobrn

drivers/gpio/gpiolib.c

@@ -2465,8 +2465,10 @@ int gpiod_request_commit(struct gpio_desc *desc, const char *label)
 		return -EBUSY;
 
 	offset = gpiod_hwgpio(desc);
-	if (!gpiochip_line_is_valid(guard.gc, offset))
-		return -EINVAL;
+	if (!gpiochip_line_is_valid(guard.gc, offset)) {
+		ret = -EINVAL;
+		goto out_clear_bit;
+	}
 
 	/* NOTE:  gpio_request() can be called in early boot,
 	 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.