Update atomicMaxFloat (#119577)
# Summary
Initially reported in https://github.com/pytorch/pytorch/issues/119320
I found that the by updating this function the nan values went away. I then created a godbolt to try and highlight the difference between the two versions:
https://godbolt.org/z/3sKqEqn4M
However they appear to always produce the same value, as the nvcc version is varied, except that the for some versions -inf is chosen and for others the correct subnormal is chosen... I am having a hard time finding an isolated test case for this but will keep working
### Update:
I added printf_statements to the the version and indeed some values/*addr contain -0.0f. Hence the reason why this update fixes the reported issue.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/119577
Approved by: https://github.com/yifuwang
