remove no-longer-needed workaround for var args
remove no-longer-needed workaround for var args

See #557

raulgrell/zig,zig-lang/zig,andrewrk/zig,andrewrk/zig,raulgrell/zig,raulgrell/zig,raulgrell/zig,zig-lang/zig,raulgrell/zig,zig-lang/zig