Vararg ABI on PowerPC

[vchuravy]

Should fix JuliaLang/julia#38628

On most platforms this doesn't make a difference, but on PPC
the callee can overrride the callers stack, see JuliaLang/julia#30821

[vchuravy]

Does indeed seem to fix the issue on PowerPC.

[vchuravy]

@Keno maybe you can take a look to double-check that I am using the Vararg correctly?

[vchuravy]

@StefanKarpinski if this looks ok to you, could you merge this?

[StefanKarpinski]

Did you edit these files manually?

[vchuravy]

Did you edit these files manually?

Yes I did.

[StefanKarpinski]

Ok, that's not ideal since these files are generated, but I don't actually know how to generate these files in the condition they were generated in and when I've tried to regenerate them I get very different results that don't work, so I think we have to essentially view this code base as no longer being something we can generate. Ideally, someone would figure out how to use Clang.jl to generate working bindings from a more recent version of Clang and libcurl in a way that satisfies the ABI on all platforms, but for now it seems fine to merge this.