zfs: merge openzfs/zfs@688514e47

Notable upstream pull request merges:
#15532 c1a47de86 zdb: Fix zdb '-O|-r' options with -e/exported zpool
#15535 cf3316633 ZVOL: Minor code cleanup
#15541 803a9c12c brt: lift internal definitions into _impl header
#15541 213d68296 zdb: show BRT statistics and dump its contents
#15543 a49087510 ZIL: Refactor TX_WRITE encryption similar to
TX_CLONE_RANGE
#15543 27d8c23c5 ZIL: Do not encrypt block pointers in lr_clone_range_t
#15549 67894a597 unnecessary alloc/free in dsl_scan_visitbp()
#15551 126efb588 FreeBSD: Fix the build on FreeBSD 12
#15563 acb33ee1c FreeBSD: Fix ZFS so that snapshots under .zfs/snapshot are
NFS visible
#15564 7bbd42ef4 Don't allow attach to a raidz child vdev
#15566 688514e47 dmu_buf_will_clone: fix race in transition back to NOFILL
#15571 30d581121 dnode_is_dirty: check dnode and its data for dirtiness

Obtained from: OpenZFS
OpenZFS commit: 688514e4704bdee4551d25960febd322ac26f297