Remove variadic args from the PROC callback types

[jackwakefield]

These changes are copied from lean_and_mean.zig

The main reason for doing this is for i386 builds, where Zig defines std.os.windows.WINAPI as Stdcall rather than C, and Zig doesn't support variadic args unless the calling convention is C.

I completely appreciate there could be a reason I'm missing as to why these are variadic though!

[GoNZooo]

I completely appreciate there could be a reason I'm missing as to why these are variadic though!

More than likely you are overestimating the amount of manual code that's written here. On top of that it's likely that Zig itself generates other code nowadays for the same thing.

Have you tried these changes out in practice?

P.S. I'm very sorry about the late reply.