Don't recreate ctx.cluster when reconnecting after installing kernels.
Don't recreate ctx.cluster when reconnecting after installing kernels.

ivotron/teuthology,SUSE/teuthology,tchaikov/teuthology,dreamhost/teuthology,SUSE/teuthology,ceph/teuthology,tchaikov/teuthology,SUSE/teuthology,ktdreyer/teuthology,ceph/teuthology,dreamhost/teuthology,caibo2014/teuthology,michaelsevilla/teuthology,zhouyuan/teuthology,yghannam/teuthology,dmick/teuthology,robbat2/teuthology,robbat2/teuthology,ivotron/teuthology,caibo2014/teuthology,t-miyamae/teuthology,dmick/teuthology,ktdreyer/teuthology,dmick/teuthology,zhouyuan/teuthology,yghannam/teuthology,t-miyamae/teuthology,michaelsevilla/teuthology