Fix build with DPDK #614

Job	Run time
build (gcc, vanilla)	1m 50s
build (gcc, dpdk)	1m 51s
build (gcc, dpdk-light)	1m 50s
build (gcc, netmap)	1m 50s
build (gcc, vanilla-nopool)	1m 49s
build (gcc, dpdk-flow-dynamic)	1m 51s
build (clang, vanilla)	1m 37s
build (clang, dpdk)	1m 52s
build (clang, dpdk-light)	1m 52s
build (clang, netmap)	1m 42s
build (clang, vanilla-nopool)	1m 36s
build (clang, dpdk-flow-dynamic)	1m 52s
mirror	0s
	21m 32s

Provide feedback