drm/panel: ilitek-ili9881c: Fix warning with GPIO controllers that sleep

In the Linux kernel, the following vulnerability has been resolved: drm/panel: ilitek-ili9881c: Fix warning with GPIO controllers that sleep The ilitek-ili9881c controls the reset GPIO using the non-sleeping gpiod_set_value() function. This complains loudly when the GPIO controller needs to sleep. As the caller can sleep, use gpiod_set_value_cansleep() to fix the issue.