regent: Fix a potential bug by ensuring that the param map is zeroed.
regent: Fix a potential bug by ensuring that the param map is zeroed.

StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion