gpio: cdev: Don't check struct gpio_chip in gpio_chrdev_open()

gpio: cdev: Don't check struct gpio_chip in gpio_chrdev_open()

It's harmless even if: chrdev_open() and cdev_device_del() run at the
same time, and gpio_chrdev_open() gets called after the underlying GPIO
chip has gone.  The subsequent file operations check the availability
of struct gpio_chip anyway.

Don't check struct gpio_chip in gpio_chrdev_open().

Reviewed-by: Linus Walleij <linusw@kernel.org>
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://patch.msgid.link/20260223061726.82161-6-tzungbi@kernel.org
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>