modify vr_compat.h to compile on centos 6.5 and later
modify vr_compat.h to compile on centos 6.5 and later

Change-Id: Ibf124cf46cf4b07b073494707ee4d0c63da2bed3

codilime/contrail-vrouter,srajag/contrail-vrouter,codilime/contrail-vrouter,codilime/contrail-vrouter,codilime/contrail-vrouter,srajag/contrail-vrouter,srajag/contrail-vrouter