[patch ada]: Last fix for PR ada/47163 on windows native hosts

[Arnaud Charlet]

> I'm one of the MSys "devs" (if you want to call the sporadic process of
> updating MSys "development").  I'll take a look at implementing
> 	ln -s file dir
> as synonymous with
> 	ln -s file dir/basename-of-file
> in the next few days.

Thanks, although the case we're really interested in here is:

   cp -p file dir
as equivalent to
   cp -p file dir/basename-of-file

Arno