When "show_other_directories" is set, that implies that we are looking
for untracked files, which obviously means that we should ignore
directories that are marked as gitlinks in the index.
This fixes "git status" in a superproject, that would otherwise always
report that subprojects were "Untracked files:"
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Junio C Hamano <junkio@cox.net>