[clang] Fixed issue #128882: don't warn if 1st argument to 'getcwd' is NULL (PR #135720)

[Balazs Benics via cfe-commits]

https://github.com/steakhal commented:

I was busy for the last few days, I apologize.
The patch looks good overall, I had one question inline.
Thank you fixing this.

https://github.com/llvm/llvm-project/pull/135720