libXrdSeckrb5-5.so library missing causing problems reading files from eos

reported on offline software mailing list. Following produces warnings in 0.3:

root -l /eos/atlas/atlascerngroupdisk/phys-higgs/HSG8/ttHbb_legacy_L2ntuples/sys_v2.5/1l/5j3b_fraction_ttb/tt_PP8_mc16a.root

See:

Plugin version SecClnt v5.5.2 is incompatible with seckrb5 v5.6.7 (must be <= 5.5.x) in sec.protocol libXrdSeckrb5-5.so