This ioctlv is used to get an IOSC decrypt handle for a title.
It is known to be used internally by the WFS modules, but it can also
be used from the PPC under some conditions.
Brings us down to 2 essentially unimplementable ioctlvs (syscalls which
seem to return kernel thread priorities...), and 1 known but
unimplemented ioctlv (VerifySign).