leds: gpio: Utilise PTR_ERR_OR_ZERO()

Avoid a boilerplate code by using PTR_ERR_OR_ZERO() in create_gpio_led().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20231016161005.1471768-2-andriy.shevchenko@linux.intel.com


Signed-off-by: Lee Jones <lee@kernel.org>