PATCH: Remove gthr-gnat.c from Linux

[Arnaud Charlet]

> The main difference may be I have a 4way 1.3GHz Itanium 2. I saw
> quite a few thread bugs which I didn't see on other machines.
> Unfortunately, I don't know anything about Ada. I can't tell if
> the Ada library is doing the right thing with thread or not.

Ada tasking has been used on lots of complex application on many
different architectures and massively parallel machines (e.g. 64 proc
machines), so it is pretty reliable.

Now, that could equally well be a libpthread bug in this case :-)

> Here is a patch to remove gthr-gnat.c from Linux.

Looks fine to me.

Arno