Make casuword() atomic for armv6
Fix .debug_line prologue header length calculation for 64-bit DWARF

The header_length field is the number of bytes following the field to
the first byte of the line number program.  The hard-coded constants
previously here (4 + 2 + 4) were correct only for 32-bit DWARF.

Sponsored by:	DARPA, AFRL
iw_cxgbe: iWARP driver for Chelsio T4/T5 chips.  This is a straight port
of the iw_cxgb4 found in OFED distributions.

Obtained from:	Chelsio
- Add relative specification in expiration time.
- Add proto3 option for RTF_PROTO3.
- Use %lu for members of struct rt_metrics.
Remove atf headers which never existed

Reviewed by:	marcel
Optimize isp(4) to reduce CPU usage, especially in target mode:
 - Remove two excessive and slow register reads from isp_intr().  Instead
of rereading value every time, assume that registers contain what we have
written there.
 - Avoid sequential search through 4096 array elements when looking for
command tag.  Use hash of lists to store active tags separately from free
ones and so greatly speedup the searches.

Reviewed by:	mjacob
- Switch to use WBWA mappings for page tables on armv6, this is needed for SMP.
- Fix PTE_SYNC() for PIPT L2 caches, using the virtual address wasn't so useful.
- Use PTE_SYNC() for >= armv6
Spell cpu_l2cache_wb_range correctly.
Eliminate unconditional debug printfs.

Linux writes to these nominally read-only registers,
so avoid having bhyve write warning messages to stdout
when the reg writes can be safely ignored. Change the
WPRINTF to DPRINTF which is conditional.

Reviewed by:	mav
Discussed with:	mav, Zhixiang Yu
MFC after:	3 days
Add lot of missed files and dirs
Changes required for OpenBSD/amd64:

- Allow a hostbridge to be created with AMD as a vendor.
  This passes the OpenBSD check to allow the use of MSI
  on a PCI bus.
- Enable the i/o interrupt section of the mptable, and
  populate it with unity ISA mappings. This allows the
  'legacy' IRQ mappings of the PCI serial port to be
  set up. Delete unused print routine that was obscuring code.
- Use the '-W' option to enable virtio single-vector MSI
  rather than an environment variable. Update the virtio
  net/block drivers to query this flag when setting up
  interrupts.: bhyverun.c
- Fix the arithmetic used to derive the century byte in
  RTC CMOS, as well as encoding it in BCD.

Reviewed by:	neel
MFC after:	3 days
Increase the KVA available for xscale CPUs.
iw_cxgbe should have a dependency on t4nex.

Reported by:	trasz@
Fix typo in previous commit.
Use long explicitly for the time difference.
- Fix a bug which prevented jails from starting when $jail_conf was used and
  no jail name was specified.
- Display error messages when start/stop fails.

Reported by:	swills
Update firmware for run(4) to version 0.33.
Fix rf registers for RT3070.
Fix lower bits of RF_R3 for RT3370 and newer.  This change doesn't affect
older chipsets.
Since the DAC issue has been fixed in RT3070(F), the voltage raising fix
is no longer needed.