dhcp: decrease read timeout and clamp backoff
dhcp: decrease read timeout and clamp backoff

kad/cni,steveeJ/cni,Symmetric/cni,NeilW/cni,squaremo/cni,rosenhouse/cni,mcastelino/cni,tomdee/cni,appc/cni,luxas/cni,NeilW/cni,containernetworking/plugins,aanm/cni,rosenhouse/cni,Symmetric/cni,tangle329/cni,containernetworking/cni,dcbw/cni,containernetworking/cni,luxas/cni,dcbw/cni,steveeJ/cni,jonboulle/cni,jonboulle/cni,aanm/cni,squeed/plugins,squeed/plugins,appc/cni,containernetworking/plugins,zenlinTechnofreak/cni,murat1985/cni,tomdee/cni,squaremo/cni,murat1985/cni,tangle329/cni,mcastelino/cni,achanda/cni,kad/cni,achanda/cni,zenlinTechnofreak/cni