drm/exynos: vidi: fix to avoid directly dereferencing user pointer

In the Linux kernel, the following vulnerability has been resolved: drm/exynos: vidi: fix to avoid directly dereferencing user pointer In vidi_connection_ioctl(), vidi->edid(user pointer) is directly dereferenced in the kernel. This allows arbitrary kernel memory access from the user space, so instead of directly accessing the user pointer in the kernel, we should modify it to copy edid to kernel memory using copy_from_user() and use it.