drm: Use sizet type for len variable in drmcopy_field()
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 v5.4.220 by commit fb282b4e8aefbb8a2849b04171ad199bdd4f4d57. For more details please see the references link.