[clang] [llvm] Clang: Add nsz to llvm.minnum and llvm.maxnum emitted from fmin and fmax (PR #113133)

[Eli Friedman via cfe-commits]

efriedma-quic wrote:

Please propose a fix for the definition of nsz itself itself in LangRef; burying an exception to the general nsz rules in the middle of the definition of min/max is, at best, confusing.

https://github.com/llvm/llvm-project/pull/113133