[clang] [Clang] Fix Sema::checkArgCount for 0-arg functions (PR #139638)

[Mariya Podchishchaeva via cfe-commits]

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@@ -168,7 +168,7 @@ bool Sema::checkArgCount(CallExpr *Call, unsigned DesiredArgCount) {
 
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Fznamznon wrote:

Maybe also assert that `ArgCount > 0`? In case `checkArgCountAtLeast` becomes broken.

https://github.com/llvm/llvm-project/pull/139638