xen: remove tests for pvh mode in pure pv paths

Remove the last tests for XENFEAT_auto_translated_physmap in pure
PV-domain specific paths. PVH V1 is gone and the feature will always
be "false" in PV guests.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>