The intention of this patch is not to break current compilations on
Xenial boxes that run with 4.4 kernel which is not supported by OVS
openvswitch kernel module. After we are confident to switch master
branch to be running on Xenial only, we will get rid of the compilation
itself until it's needed by other features.
Change-Id: I1c890bf5a6564a69e36b8289a5d8dc0deee2a429
fa5e23cbe6