[fpc-pascal] ExpandFileName failure on long filenames on Linux

[Marco van de Voort]

In our previous episode, Bart said:
> > As I wrote -
> > the other file and directory related functions and procedures have
> > always had only shortstring interfaces, whereas with GetDir there has
> > also been the ansistring version).
> 
> I would prefer waiting for _all_ IO functions to handle LongStrings
> (or any not_shortstring).

That was the original idea, removing the shortstring versions for not
embedded targets, so that nobody accidentally could call shortstring
versions.  (and only find out runtime)

But that was deemed to confusing, so now both sets are back again.