Notable upstream pull request merges:
#1594041ae864b6 Replace P2ALIGN with P2ALIGN_TYPED and delete P2ALIGN
#161285137c132a zpool import output is not formated properly
#16138efbef9e6c FreeBSD: Add zfs_link_create() error handling
#1614604bae5ec9 Disable high priority ZIO threads on FreeBSD and Linux
#16151cc3869153 zfs_ioc_send: use a dedicated taskq thread for send
#16151adda768e3 spa: remove spa_taskq_dispatch_sync()
#16151515c4dd21 spa: flatten spa_taskq_dispatch_ent()
#161510a543db37 spa_taskq_dispatch_ent: simplify arguments
#16153975a13259 Add support for parallel pool exports
#1615389acef992 Simplified the scope of the namespace lock
#16159136c05321 ZAP: Fix leaf references on zap_expand_leaf() errors
#16162af5dbed31 Fix scn_queue races on very old pools
#161653400127a7 Fix ZIL clone records for legacy holes
#16167414acbd37 Unbreak FreeBSD cross-build on MacOS broken in 051460b8b#16172eced2e2f1 libzfs: Fix mounting datasets under thread limit pressure
#16178b64afa41d Better control the thread pool size when mounting datasets
#16181fa99d9cd9 zfs_dbgmsg_print: make FreeBSD and Linux consistent
#16191e675852bc dbuf: separate refcount calls for dbuf and dbuf_user
#16198a043b60f1 Correct level handling in zstream recompress
#1620434906f8bb zap: reuse zap_leaf_t on dbuf reuse after shrink
#16206d0aa9dbcc Use memset to zero stack allocations containing unions
#162078865dfbca Fix assertion in Persistent L2ARC
#1620808648cf0d Allow block cloning to be interrupted by a signal
#16210e2357561b FreeBSD: Add const qualifier to members of struct
opensolaris_utsname
#16214800d59d57 Some improvements to metaslabs eviction
#1621602c5aa9b0 Destroy ARC buffer in case of fill error
#1622501c8efdd5 Simplify issig()
Obtained from: OpenZFS
OpenZFS commit: e2357561b9
aca928a50a