For AMD SEV provide ioctl(2) in cpp(4) to shutdown guest.

For AMD SEV provide ioctl(2) in cpp(4) to shutdown guest.

To shutdown a SEV-enabled guest, first deactivate the guest context
in ccp(4), then decommission the guest context.  Combine these two
operations in a single ioctl to simplify guest shutdown for vmd(8).
As this ioctl does not directly map to a single ccp command, use a
high number for the ioctl.  More ioctls like this one will come.

from hshoexer@; OK mlarkin@