hurd: Fix O_DIRECTORY | O_NOFOLLOW

hurd: Fix O_DIRECTORY | O_NOFOLLOW

Appending / to the path to be looked up would make us always follow a final
symlink, even with O_NOTRANS (since the final resolution is after the
'/').  In the O_DIRECTORY | O_NOFOLLOW case, we thus have to really open
the node and stat it, which we already do anyway, and check for
directory type.

Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Gbp-Pq: Topic hurd-i386
Gbp-Pq: Name git-NOFOLLOW-DIRECTORY.diff