xen: list interfaces subject to the security process exception in XSA-77

xen: list interfaces subject to the security process exception in XSA-77

List all the sub ops of:
  __HYPERVISOR_domctl
  __HYPERVISOR_sysctl
  __HYPERVISOR_memory_op
  __HYPERVISOR_tmem_op
which are subject to the policy given in
http://xenbits.xen.org/xsa/advisory-77.html

It is expected that these lists will be whittled away as each interface is
audited for safety.

New interfaces should be expected to be safe when introduced (IOW the list
should never be expanded).

This is XSA-77.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>