ln: creating hard link `f' => `f': No such file or directory
* src/ln.c (do_link): Give a better diagnostic in this unusual case.
(do_link): Rename local: s/lstat_ok/dest_lstat_ok/.
* tests/ln/Makefile.am (TESTS): Add hard-backup.
* tests/ln/hard-backup: New test for the above.
Jim Meyering