Add a test case for PR kern/48787.
Add the missing ETC0, ETC6, ETC7, ETC8 `gpio' registers. They are special in
that they can't be set/unset nor configured. The only changeable parameters
are the pullups PUD and the DRV driving strength. They however fit the same
structure as the rest of the GPIOs and are used as such.
Define and implement device_register_post_config() hook analog to the
device_register() hook.

Already found on sparc64 and librump. Tested compilation and running of
machines with and without the hook defined.
Implement evbarm_device_register_post_config() hook for odroid and its
decendents. This allows post attach actions on every level of the machine
support.
No use in duplicating the frequency settings of mct and gtmr at two different
places.
The Odroids USB hub and Ethernet init are not to be done at the SoC level.
Fix typo
Get the Odroid-U3 USB hub working! It now attaches and /lists all its children
like mouse etc.
Add a history function that takes a FILE pointer; needed for Capsicum.
From Eitan Adler
Provide a non-EHABI version of the mcount glue.
Support DWARFish unwind for ARM.
Deal with incompatible cache aliases. Specifically,

- always flush an ephemeral page on unmap
- track unmanaged mappings (mappings entered via pmap_kenter_pa) for
  aliases where required and handle appropriately (via pmap_enter_pv)

Hopefully this (finally) addresses the instability reported in the
following PRs:

PR/44900 - R5000/Rm5200 mips ports are broken
PR/46890 - upcoming NetBSD 6.0 release is very unstable / unusable on cobalt qube 2
PR/48628 - cobalt and hpcmips ports are dead
Add An to authors. Wording.
kill unused array split
Belatedly adapt to changes in the code.
stmt;; -> stmt;
Fix newline problem which was added in previous commit.
acpi_md_findoverride is only used when NIOAPIC > 0, so don't provide it
otherwise.
Use macro.
buf is only used in the ioapic case.