metricd: no max wait, fix comment
metricd: no max wait, fix comment

Change-Id: I3aad55628652e231c984d1d3fd34d7432397a626

leandroreox/gnocchi,sileht/gnocchi,gnocchixyz/gnocchi,sileht/gnocchi,leandroreox/gnocchi,gnocchixyz/gnocchi