[llvm] [NVPTX] Add support for atomic add for f16 type (PR #84295)

[Adrian Kuegel via llvm-commits]

akuegel wrote:

Ok, I found something in NVPTXISelDagToDag.cpp, seems like there is no hex representation for f16 constants, and it is replaced by loading from a f16 register. Is this the right place where to look further?

https://github.com/llvm/llvm-project/pull/84295