scsi: virtio_scsi: always read VPD pages for multiqueue too

commit a680f1d463aeaeb00d22af257a56e111967c2f18 upstream.

Multi-queue virtio-scsi uses a different scsi_host_template struct.  Add
the .device_alloc field there, too.

Fixes: 25d1d50e23275e141e3a3fe06c25a99f4c4bf4e0
Cc: stable@vger.kernel.org
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>