vlib: Fix WARN-ING macro in function
vlib: Fix WARN-ING macro in function

Change-Id: I238106c2afc46904fb0eb17164f30dbd1378892e
Signed-off-by: Mohsin Kazmi <3be96aed1fe21f963e790909e1d3a8e57ce776f2@cisco.com>

chrisy/vpp,vpp-dev/vpp,FDio/vpp,chrisy/vpp,vpp-dev/vpp,vpp-dev/vpp,chrisy/vpp,chrisy/vpp,FDio/vpp,chrisy/vpp,vpp-dev/vpp,FDio/vpp,vpp-dev/vpp,FDio/vpp,vpp-dev/vpp,FDio/vpp,vpp-dev/vpp,FDio/vpp,FDio/vpp,chrisy/vpp,FDio/vpp,chrisy/vpp,chrisy/vpp