drm/panel: ili9341: fix optional regulator handling
This is an automated ID intended to aid in discovery of potential security vulnerabilities. The actual impact and attack plausibility have not yet been proven. This ID is fixed in Linux Kernel version v5.16.20 by commit e3d982c111a6c033671dd6084b07f62fbf50f76f, it was introduced in version v5.15 by commit 5a04227326b04c15b015181772f5c853172fdb68. For more details please see the references link.