[fpc-pascal]Drive detection unit (final)

[Aitor Santamaría Merino]

Hi all,

In the end, I managed to "re-study" the drive detection DOS routines,
and mange to compose a small unit, that is able to distinguish between
CD, HD, FD, net, ram, substed and doublespace-compressed drives.

It works for me now, and has been put into a clear pascal source file.
Let me know if you want to use it or give it a try. I would also be
happy to contribute it for whatever "official" stuff or package were it
could be used (for some reason, Marco's original routines at EDOS don't
work for me, but as I haven't heard any other feedback, I don't know if
it was just me, or there is a small bug or whatever in EDOS; should my
unit be neccessary, please, ask for it, unfortunately, I don't have much
time to write up a page and website to post it).

(Marco: it looks now clearer, if you want to have a look at them).

Aitor