od ms conversion and ceil should happen even for nomod

[Francesco149]

https://osu.ppy.sh/b/703177

od8.2 and od8.3 have the same 300 ms value in-game with both DT and nomod
currently oppai only does this correctly on DT

not a big difference but worth fixing

pretty interesting that some fractional od's are the same as far as pp goes but play slightly differently (50, 100 ms are different even though 300ms is the same which is what is used to compute the od value for pp)