pds_vdpa: move enum from common to adminq header

The pds_core_logical_qtype enum and IFNAMSIZ are not needed
in the common PDS header, only needed when working with the
adminq, so move them to the adminq header.

Note: This patch might conflict with pds_vfio patches that are
      in review, depending on which patchset gets pulled first.

Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20230519215632.12343-5-shannon.nelson@amd.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>