Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

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

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

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

Add ID for Nuvoton WPCM450RA0BX found on Supermicro X9SCA-F motherboards.

While I'm there, also make this driver to attach to devices that have
an unknown device ID.

MFC after: 1 month

Add DEVICE_IDENTIFY method for wbwd(4), required on most of recent
Supermicro motherboards.

Tested on X8STi and X8DTH boards.

Sponsored by: iXsystems, Inc.
MFC after: 2 weeks

Use DEVMETHOD_END.

MFC after: 2 weeks

sbuf_trim() cannot be used on sbuf with drain function set.
This fixes panic when listing sysctls on INVARIANTS-enabled kernel while
having wbwd loaded.

This panic was not fatal, at worst one additional space was printed.

Also sbuf_trim() makes some sense even if drain function is set. The drain
function is called only when buffer is to be expanded. So we could still trim
existing buffer before drain is called. In this case it worked just fine - the
trailing space was correctly trimmed.

Obtained from: WHEEL Systems
MFC after: 1 week

Add device ids for the Winbond 83627DHG-P chip and set the registers to
trigger the keyboard reset line on timeout.

Reviewed by: bz
MFC after: 1 week

Fix a typo in wbwd so that CRF5 is actually written to the data register
rather than the index register.

Reviewed by: bz
MFC after: 3 days

Provide wbwd(4), a driver for the watchdog timer found on various
Winbond Super I/O chips.

With minor efforts it should be possible the extend the driver to support
further chips/revisions available from Winbond. In the simplest case
only new IDs need to be added, while different chipsets might require
their own function to enter extended function mode, etc.

Sponsored by: Sandvine Incorporated ULC (in 2011)
Reviewed by: emaste, brueffer
MFC after: 2 weeks