virtio: fix the index issue
virtio: fix the index issue

Type: fix

Fixes: 587f9130424fd451e4ba823240d02f655fb197d1

Change-Id: I230993a54c84e22e324de2a8defeda83c517d733
Signed-off-by: Mohsin Kazmi <3be96aed1fe21f963e790909e1d3a8e57ce776f2@cisco.com>

chrisy/vpp,FDio/vpp,chrisy/vpp,FDio/vpp,chrisy/vpp,FDio/vpp,chrisy/vpp,FDio/vpp,FDio/vpp,chrisy/vpp,FDio/vpp,chrisy/vpp,FDio/vpp,chrisy/vpp,FDio/vpp,chrisy/vpp