netlink: fix Python 2 compatibility
netlink: fix Python 2 compatibility

Bug-Url: https://github.com/svinota/pyroute2/pull/176

roolebo/pyroute2,drzaeus77/pyroute2,drzaeus77/pyroute2,tomislacker/python-iproute2,mtiny/pyroute2,vodik/pyroute2,vodik/pyroute2,tomislacker/python-iproute2,simudream/pyroute2,simudream/pyroute2,mtiny/pyroute2,roolebo/pyroute2