Revert r252694 - which attempted to fix bit emulation for armv6/armv7.

This seems to cause issues with jemalloc + {dhclient, sshd}.

Thus, revert this for now until the root cause can be found and
fixed.

This should quieten some runtime problems with the Raspberry Pi.

PR: kern/185046
MFC after: 3 days
Modify handling of write to the vlapic SVR register.

The handler is now called after the register value is updated in the virtual
APIC page. This will make it easier to handle APIC-write VM-exits with APIC
register virtualization turned on.

Additionally, mask all the LVT entries when the vlapic is software-disabled.
Fixing build bustage.
Add D-Link DWA-140 rev D1, another RT5372/run(4).
From Anton Mazunin.
Regen.
In sys/amd64/vmm/intel/vmx.c, silence a (incorrect) gcc warning about
regval possibly being used uninitialized.

Reviewed by:	neel
Address some warnings which showed up on the userland version.

MFC after: 1 week
gcc: merge small upstream change.

Backport from mainline:
2007-04-24  Hui-May Chang <hm.chang@apple.com>

* reload1.c (merge_assigned_reloads) : Do not merge a RELOAD_OTHER
instruction with a RELOAD_FOR_OPERAND_ADDRESS instruction.

Obtained from:	gcc 4.3 (rev. r124115: GPLv2)
MFC after:	1 week
sh: Don't check input for non-whitespace if history is disabled.

preadbuffer() maintained a flag whether there was any non-whitespace
character. This flag is only useful when history is enabled (in that case,
lines containing only whitespace are not added to history). Instead, check
using strspn() when history is enabled.

There is an approximate 2% speedup when running
  sh -c '. /etc/rc.subr; . /etc/defaults/rc.conf; source_rc_confs'
with hot cache.
Improve wording slightly.
- Fix EBADF description, in following the future POSIX tc and what FreeBSD
  actually implements.
- Improve grammar: use more preferred "can", not "could".

Submitted by:	jilles
Do not coalesce stack entry, vm_map_stack() asserts that the requested
region is claimed by a new entry.

Pass MAP_STACK_GROWS_DOWN and MAP_STACK_GROWS_UP flags to
vm_map_insert() from vm_map_stack(), to really turn off coalescing
code and call to vm_map_simplify_entry() [1].

Reported by:	avg, peter, many
Tested by:	avg, peter
Noted by:	avg [1]
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Revert r259200.  There are geoms/drivers which do not update
bio_completed, only manage bio_resid, e.g. sa(4).

Reported and tested by:	Manfred Antar <null@pozo.com>
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Fix accounting for the negative cache entries when reusing v_cache_dd.
Having ncneg diverge with the actual length of the ncneg tailq causes
NULL dereference.

Add assertion that an entry taken from ncneg queue is indeed negative.

Reported by and discussed with:	avg
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Move build_doc_ports() to the if...fi block from which it is called.

Sponsored by:	The FreeBSD Foundation
Add the scaffolding for minidumps. They're just like physical dumps,
except the chunks aren't physical memory regions but virtual memory
regions. In both cases, the core file is an ELF file and flags in
the header allow libkvm to distinguish one from the other.
Modify handling of writes to the vlapic ICR_TIMER, DCR_TIMER, ICRLO and ESR
registers.

The handler is now called after the register value is updated in the virtual
APIC page. This will make it easier to handle APIC-write VM-exits with APIC
register virtualization turned on.

We can no longer rely on the value of 'icr_timer' on the APIC page
in the callout handler. With APIC register virtualization the value of
'icr_timer' will be updated by the processor in guest-context before an
APIC-write VM-exit.

Clear the 'delivery status' bit in the ICRLO register in the write handler.
With APIC register virtualization the write happens in guest-context and
we cannot prevent a (buggy) guest from setting this bit.
Tighten default restrictions for ntpd(8) server and provide a link
to NTP access restriction documentation.

The new default restrictions would allow only time queries from a
remote system and will KoD all other requests, but still allow
localhost to do make all requests.

These restrictions are also recommended for all Internet-facing
public NTP servers.

This changeset is intended for an instant MFC to stable/10 and
releng/10.0.
Modify handling of writes to the vlapic LVT registers.

The handler is now called after the register value is updated in the virtual
APIC page. This will make it easier to handle APIC-write VM-exits with APIC
register virtualization turned on.

This also implies that we need to keep a snapshot of the last value written
to a LVT register. We can no longer rely on the LVT registers in the APIC
page to be "clean" because the guest can write anything to it before the
hypervisor has had a chance to sanitize it.
Implement cross build support for embedded devices into
release.sh:

 - Modify release/release.sh to recognize an 'EMBEDDEDBUILD'
   variable.  When set, release/release.sh will build the chroot
   userland as is done for big-iron builds.

 - Instead of running the 'buildworld', 'buildkernel', and
   'release' targets in the chroot, a separate script is run.
   The script tools/release/${XDEV}/release.sh sets up the rest
   of the chroot workspace, such as installing ports that will
   be needed, and building the 'xdev' target.

 - crochet (by kientzle@) is checked out from the upstream
   repository (and if needed, u-boot, in the case of Raspberry
   Pi).

 - tools/release/${XDEV}/release.sh then runs crochet with
   a configuration file specific to the ${KERNCONF} being built.

Note that this is effectively a first-pass attempt to integrate
this into the release process.

Tested against:	head@r259961
Sponsored by:	The FreeBSD Foundation