These commits reduce the number of directory entries traversed by
optimizing empty entry hint.

Changes for v2:
  - [1/2]
    - add exfat_reset_empty_hint()
    - rename exfat_hint_empty_entry() to exfat_set_empty_hint()
    - remove the condition `ei->hint_femp.count < num_entries`
  - [2/2]
    - Check the empty entries after unused entry in
      exfat_search_empty_slot()

Yuezhang Mo (2):
  exfat: simplify empty entry hint
  exfat: hint the empty entry which at the end of cluster chain

 fs/exfat/dir.c   | 76 +++++++++++++++++++++++++++++++-----------------
 fs/exfat/namei.c | 33 +++++++++++++--------
 2 files changed, 70 insertions(+), 39 deletions(-)

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2.25.1