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

[Rahul Joshi via cfe-commits]

jurahul wrote:

> LGTM

Thanks. I'll split out an additional PR for the independent fixes, and then in this one I'll change ENABLE_VALIDATION back to 0 and also remove the `formatvv()` and use `formatv(false` instead so we just have one function name.

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