dpdk: fix ipsec coverity warnings
dpdk: fix ipsec coverity warnings

CID 161044 and 161045

Change-Id: I50a450e231e387f05e354e3b07dc777ab864d018
Signed-off-by: Sergio Gonzalez Monroy <efb28dd1236fe58fb57f933212eddfe89b9da704@intel.com>

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