When moving "up" the hierarchy, be careful to remove a just-emptied

When moving "up" the hierarchy, be careful to remove a just-emptied
directory before opening ".", to avoid trouble with file system
implementations that cache readdir results at opendir-time.
* src/remove.c (AD_pop_and_chdir): Add a file descriptor parameter.
Don't update **DIRP.  Don't call fdopendir here.
(remove_dir): Call fdopendir here instead.
Report and patch from Mikulas Patocka:
<http://lists.gnu.org/archive/html/bug-coreutils/2006-12/msg00170.html>