export fseeko() and ftello() patch

[Corinna Vinschen]

> The attached patch exports newlib's fseeko() and ftello().  Besides

Applied, thanks. 

Note, though, that this isn't the ultimate solution.  In the long run we
must write our own entry points for 32 bit as well as 64 bit off_t.  The
problem is that newlib is still not changed to support both off_t types
on the FILE-I/O function level.  Sigh.

Corinna