ft2232_spi: Add support for Google Servo boards (v1 + v2)

This patch has been cherry-picked from various patches in the chromiumos
tree denoted below.

Change-Id: I4b679e23ab37a4357b1e3d23f6f65a1c31f7d71a
Change-Id: Ibda56201ab4519315431c08206c61ceffb7c7e65
Change-Id: I540ad2d304dc69a7c79ca154beb744ef947ff808

Servo V2 has two FT4232H parts. The first one (denoted 'legacy') is
dedicated to supporting orginal Servo V1 functionality. The second,
residing at USB ID 0x18d1:5003 provides two other SPI interfaces on
port A and B respectively.

Additional changes by Alexandru Gagniuc, Hatim Kanchwala and Urja Rannikko:

 - The clock divisor is set to '6', as this creates a 10MHz SPI clock,
   which is the same SPI clock that the chromiumos branch produced.
 - Add udev rule for Google servo boards to util/flashrom.rules.
 - Add Google servo entry to manpage.

Corresponding to flashrom svn r1925.

Signed-off-by: Todd Broch <tbroch@chromium.org>
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Signed-off-by: Hatim Kanchwala <hatim@hatimak.me>
Signed-off-by: Urja Rannikko <urjaman@gmail.com>
Acked-by: Hatim Kanchwala <hatim@hatimak.me>
Acked-by: Urja Rannikko <urjaman@gmail.com>
Acked-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>
3 files changed