regress: diff.pl - check mtime on directories with --mtime-dir, add support for pipe, char and block file
regress: diff.pl - check mtime on directories with --mtime-dir, add support for pipe, char and block file

Depending on the restore order, a directory could be restored before a
file inside it. The resulting mtime could be wrong.

Add support for special files like named pipe, char and block special devices.

rkorzeniewski/bacula,rkorzeniewski/bacula,rkorzeniewski/bacula,rkorzeniewski/bacula,rkorzeniewski/bacula,rkorzeniewski/bacula,rkorzeniewski/bacula,rkorzeniewski/bacula