hdf5: fix off-by-1 error in extent calculation
hdf5: fix off-by-1 error in extent calculation

StanfordLegion/legion,sdalton1/legion,StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion,chuckatkins/legion,sdalton1/legion,sdalton1/legion,StanfordLegion/legion,chuckatkins/legion,chuckatkins/legion,sdalton1/legion,chuckatkins/legion,sdalton1/legion,chuckatkins/legion,StanfordLegion/legion,StanfordLegion/legion,sdalton1/legion,chuckatkins/legion,chuckatkins/legion