virtio: add the buffer allocation error
virtio: add the buffer allocation error

Type: improvement

Change-Id: I991e32d531719693c387db4ef93d04d4b562789d
Signed-off-by: Mohsin Kazmi <3be96aed1fe21f963e790909e1d3a8e57ce776f2@cisco.com>

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