[clang] [llvm] [transforms] Inline simple variadic functions (PR #81058)

[Simon Pilgrim via cfe-commits]

RKSimon wrote:

Why have the x86 tests been placed in test\CodeGen\X86 instead of something like test\Transforms\ExpandVariadics\X86 ?

https://github.com/llvm/llvm-project/pull/81058