[clang] [lldb] [llvm] [mlir] [Support] Validate number of arguments passed to formatv() (PR #105745)

[Rahul Joshi via cfe-commits]

jurahul wrote:

Hi all, this is related to https://discourse.llvm.org/t/adding-argument-count-validation-for-formatv/80876/1

I still have formatv() and formatvv() functions in the code, but only a handful instances. So, if this looks ok overall, I will go ahead and rename formatvv() to formatv_unchecked() (or if there are other better suggestions for that version). Also, let me know if it would make sense to split this into 2 changes, one NFC one that fixes formatv() current uses that are invalid, and then the next one that adds validation and changes the handful few that need to be to formatvv().

https://github.com/llvm/llvm-project/pull/105745