Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC r256125:
Make isci(4) loadable.

MFC r239545, r239665:

Fix/add support for SCSI UNMAP to ATA DSM translation.

This addresses kernel panic observed when sending SCSI UNMAP
commands to SATA disks attached to isci(4).

1) Flesh out callback routines to allocate/free buffers needed for
translating SCSI UNMAP data to ATA DSM data.
2) Add controller-level pool for storing buffers previously allocated
for UNMAP translation, to lessen chance of no buffer available
under memory pressure.
3) Ensure driver properly handles case where buffer pool is empty
and contigmalloc returns NULL.
4) Clear freeze bit in isci_remote_device_release_lun_queue() before
calling xpt_release_devq to ensure that any ccbs which immediately
start during the call to xpt_release_devq() see an accurate picture
of the frozen_lun_mask. This code path is extensively exercised
when tagged read/write commands mix with non-tagged DSM commands.

Sponsored by: Intel

MFC r232225

Update PCI-IDs with devices found on Intel SDP

Return BUS_PROBE_DEFAULT so that non-default drivers may be loaded

MFC r230843, r231134, r231136, r231137, r231296

Add isci(4) driver for amd64 and i386 targets.

The isci driver is for the integrated SAS controller in the Intel C600
(Patsburg) chipset. Source files in sys/dev/isci directory are
FreeBSD-specific, and sys/dev/isci/scil subdirectory contains
an OS-agnostic library (SCIL) published by Intel to control the SAS
controller. This library is used primarily as-is in this driver, with
some post-processing to better integrate into the kernel build
environment.

isci.4 and a README in the sys/dev/isci directory contain a few
additional details.

This driver is only built for amd64 and i386 targets.

Sponsored by: Intel
Reviewed by: scottl
Approved by: scottl

Add isci(4) driver for amd64 and i386 targets.

The isci driver is for the integrated SAS controller in the Intel C600
(Patsburg) chipset. Source files in sys/dev/isci directory are
FreeBSD-specific, and sys/dev/isci/scil subdirectory contains
an OS-agnostic library (SCIL) published by Intel to control the SAS
controller. This library is used primarily as-is in this driver, with
some post-processing to better integrate into the kernel build
environment.

isci.4 and a README in the sys/dev/isci directory contain a few
additional details.

This driver is only built for amd64 and i386 targets.

Sponsored by: Intel
Reviewed by: scottl
Approved by: scottl

Add all isci driver source code to sys/dev/isci for the Intel C600
(Patsburg) integrated SAS controller.

sys/dev/isci contains all files specific to FreeBSD.
sys/dev/isci/scil contains OS-agnostic library maintained by Intel and
modified to best integrate into FreeBSD kernel build environment.

Sponsored by: Intel
Reviewed by: scottl