x86/PVH: permit more physdevop-s to be used by Dom0

x86/PVH: permit more physdevop-s to be used by Dom0

Certain notifications of Dom0 to Xen are independent of the mode Dom0 is
running in. Permit further PCI related ones (only their modern forms).
Also include the USB2 debug port operation at this occasion. While
largely relevant for the latter, drop the has_vpci() part of the
conditional as redundant with is_hardware_domain(): There's no PVH Dom0
without vPCI.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>