MFC 256274:
Ignore attempts to set the nmbcluster sysctls to their current value
rather than failing with an error.
MFC 257006

sbin/geom/class/part/geom_part.c
        Always validate the return of find_geomcfg().  It could be NULL, for
        example when the geom is withering.

Approved by:	ken(mentor)
Sponsored by:	Spectra Logic Corporation
MFC r249622:
Make siis(4) and mvs(4) send bus_get_dma_tag() requests to parent buses
passing real bus' child pointers instead of grandchilds.
MFC r244981 (by jfv)
Add Intel Lynx Point PCH SMBus Device IDs
MFC r253475 (by jfv):
Add new Coleto Creek device support: SATA, SMBus, and Watchdog devices.
MFC r253647:
Decode some bits defined in AHCI 1.3.1 Device Sleep Technical Proposal.
For now this is only conmetics to report HBA capabilities (Haswell?).
MFC r254987 (by gavin):
Support the PCI-Express SSD in the new MacBook Air (model A1465)
MFC r250576 (by eadler):
Fix several typos

PR:		kern/176054
MFC r253644:
Add missing NULL check after malloc(M_NOWAIT).
MFC r249065 (by trasz):
Fix locking problem in ctl_maintenance_in() - one cannot use M_WAITOK or call
ctl_done() with mutex held.
MFC r254378 (by trasz):
Turn comments about locking into actual lock assertions.
MFC r254787:
Remove locking from taskqueue_member().  The list of threads is static
during the taskqueue life cycle, so there is no need to protect it,
taking quite congested lock several more times for each ZFS I/O.
MFC r239710 (by glebius):
Fix function name in keg_cachespread_init() assert.
MFC r240676 (by glebius):
If caller specifies UMA_ZONE_OFFPAGE explicitly, then do not waste memory
in an allocation for a slab.
MFC r246087 (by glebius):
Fix typo in debug printf.
Merge branch 'stable/9' into feature/fusefs-backport/stable/9