[PATCH] Also install data-directory into the build directory as computed by relocate_gdb_directory

[Joel Brobecker]

> I've thought of one more option: we can compile two near copies of
> gdb:

I have thought of that too, but Jan worked pretty hard to reduce
the amount of time required to build GDB by removing the creation
of libgdb.a, and the build of gdbtui. Each of those step was probably
taking the amount of time it takes to link GDB. I don't think
we'll agree to regress in that respect just so that I can run GDB
without having to install...

-- 
Joel