[backport] Fix gamma neg log likelihood. (#7275)#7285

Merged

trivialfis merged 1 commit intodmlc:release_1.5.0from trivialfis:backport-fix-gamma-nloglik

Oct 5, 2021

+32-4

Commits on Oct 5, 2021

Fix gamma neg log likelihood. (dmlc#7275 )
trivialfis
committed