Refine Flash Component descriptor handling.

Possible values as well as encodings have changed in newer chipsets as follows.
 - Pre-PCH (i.e. ICH) chipsets had a maximum frequency of 33 MHz for all
   operations
 - Since Cougar Point the chipsets support dual output fast reads (encoded
   in bit 30).
 - Flash component density encoding has changed from 3 to 4 bits with Lynx
   Point, currently allowing for up to 64 MB chips.

Signed-off-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>
Acked-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>

git-svn-id: svn://flashrom.org/flashrom/trunk@1843 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1
Add support for Intel Silvermont: Bay Trail, Rangeley and Avoton.

The core of this patch to support Bay Trail originally came from the
Chromiumos flashrom repo and was modified by Sage to support the
Rangeley/Avoton parts as well.
Because that was not complicated enough already Stefan Tauner refactored
and refined everything. Bay Trail seems to be the first Atom SoC able to
support hwseq. No SPI Programming Guide could be obtained so it is
handled similarly to Lynx Point which seems to be its nearest relative.

Signed-off-by: Duncan Laurie <dlaurie@chromium.org>
Signed-off-by: Martin Roth <gaumless@gmail.com>
Signed-off-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>
Tested-by: Marc Jones <marcj303@gmail.com>
Tested-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>
Tested-by: Thomas Reardon <thomas_reardon@hotmail.com>
Tested-by: Wen Wang <wen.wang@adiengineering.com>
Acked-By: Marc Jones <marcj303@gmail.com>
Acked-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>

git-svn-id: svn://flashrom.org/flashrom/trunk@1844 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1
Add support for Intel Wildcat Point PCH.

The Wildcat Point PCH can be paired with Broadwell or Haswell.
This patch was essentially backported from ChromiumOS commit 9bd2af8.

Signed-off-by: Duncan Laurie <dlaurie@chromium.org>
Signed-off-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>
Acked-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>

git-svn-id: svn://flashrom.org/flashrom/trunk@1845 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1