[llvm] Support non-malloc functions in malloc+memset->calloc fold (PR #138299)

[via llvm-commits]

clubby789 wrote:

My mistake, I misread the definition. Would it make more sense to have a different attribute for calloc-like functions that have their arguments remapped (`alloc-calloc-variant` perhaps?). Or a more general system allowing specific mappings to be described 

https://github.com/llvm/llvm-project/pull/138299