Go: sort: function names should be mixed caps

[cia-rana]

According to Effective Go, function names should be mixed caps, but *_func including the underscore is used for the ones in sort/zfuncversion.go generated by sort/genzfunc.go. Thus when generating these functions, we should use Func instead of _func.

[ALTree]

Thanks for the report.

The suggestions in the Effective Go document do not really apply to auto-generated code. In fact, I suspect the _func prefix was chosen exactly to make the functions look like they are auto-generated (as they are).

[robpike]

This is generated code. Such code is often non-conformant stylewise.