Add support for "Butterfly" Chromebook

We're happy to announce coreboot support for the "Butterfly"
Chromebook, a.k.a HP Pavilion Chromebook.

More information at:
http://www.google.com/intl/en/chrome/devices/hp-pavilion-chromebook.html

This commit also includes support for the ENE KB3940Q embedded controller
running on Quanta's firmware.

Change-Id: I194f847a94005218ec04eeba091c3257ac459510
Signed-off-by: Stefan Reinauer <reinauer@google.com>
Reviewed-on: http://review.coreboot.org/2359
Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
Tested-by: build bot (Jenkins)
39 files changed