drm/radeon: fix potential buffer overflow in ni_set_mc_special_registers()

drm/radeon: fix potential buffer overflow in ni_set_mc_special_registers()

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 v5.19.2 by commit 9faff03617afeced1c4e5daa89e79b3906374342, it was introduced in version v3.11 by commit 69e0b57a91adca2e3eb56ed4db39ab90f3ae1043. For more details please see the references link.