Pull btrfs fixes from David Sterba:

 - fiemap fixes:
      - add missing path cache update
      - fix processing of delayed data and tree refs during backref
        walking, this could lead to reporting incorrect extent sharing

 - fix extent range locking under heavy contention to avoid deadlocks

 - make it possible to test send v3 in debugging mode

 - update links in MAINTAINERS

* tag 'for-6.1-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  MAINTAINERS: update btrfs website links and files
  btrfs: ignore fiemap path cache if we have multiple leaves for a data extent
  btrfs: fix processing of delayed tree block refs during backref walking
  btrfs: fix processing of delayed data refs during backref walking
  btrfs: delete stale comments after merge conflict resolution
  btrfs: unlock locked extent area if we have contention
  btrfs: send: update command for protocol version check
  btrfs: send: allow protocol version 3 with CONFIG_BTRFS_DEBUG
  btrfs: add missing path cache update during fiemap