vt_ioctl: fix array_index_nospec in vt_setactivate
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 v5.4.180 by commit ae3d57411562260ee3f4fd5e875f410002341104. For more details please see the references link.