Obsolete RETSIGTYPE

[Julien ÉLIE]

>> Should we keep it or should we remove AC_TYPE_SIGNAL and replace RETSIGTYPE
>> by void in INN source code?
>
> We should go ahead and do that.  INN already won't built on any system old
> enough to have a different return value.

Then let's go.  I'm changing them to "void".

-- 
Julien ÉLIE

« Women are a decorative sex.  They never have anything to say,
  but they say it charmingly. » (Oscar Wilde, _The Picture of Dorian Gray_, IV)