gpio: uapi: comment consistency

Make debounce_period_us field documentation consistent with other fields
in the union.
Signed-off-by: NKent Gibson <warthog618@gmail.com>
Reviewed-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20201005070329.21055-3-warthog618@gmail.comSigned-off-by: NLinus Walleij <linus.walleij@linaro.org>

include/uapi/linux/gpio.h

@@ -98,7 +98,7 @@ struct gpio_v2_line_values {
  * identifying which field of the attribute union is in use.
  * @GPIO_V2_LINE_ATTR_ID_FLAGS: flags field is in use
  * @GPIO_V2_LINE_ATTR_ID_OUTPUT_VALUES: values field is in use
- * @GPIO_V2_LINE_ATTR_ID_DEBOUNCE: debounce_period_us is in use
+ * @GPIO_V2_LINE_ATTR_ID_DEBOUNCE: debounce_period_us field is in use
  */
 enum gpio_v2_line_attr_id {
 	GPIO_V2_LINE_ATTR_ID_FLAGS		= 1,