generic/527: add additional test including a file with a hardlink

Add a similar test to the existing one but with a file that has a
hardlink as well. This is motivated by a bug found in btrfs where
a fsync on a file that has the old name of another file results
in the logging code to hit an infinite loop. The patch that fixes
the bug in btrfs has the following subject:

  "Btrfs: fix infinite loop during fsync after rename operations"

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>
2 files changed