[clang] [llvm] [SPIR-V] Enable variadic function lowering for the SPIR-V target (PR #175076)

[Joseph Huber via cfe-commits]

jhuber6 wrote:

> May be it's worth to disable this pass outside of the SPIR-V-for-compute compilation path.

Is there an easy way to detect this? Like a module flag?

https://github.com/llvm/llvm-project/pull/175076