raiden_debug: Upstream ChromiumOS servo debug board prog

Initial check-in of the Raiden debugger programmer for the ChromiumOS
servo debug tool. This then allows upstream flashrom to fully support
the servo debug hardware tool.

Servo is a debug board used for Chromium OS test and development.
Depending on the version of Servo, it can connect to a debug header
or USB port on the Chrome OS device. Servo is a key enabler for
testing:

 * Software access to device GPIOs, through hdctools,
 * Access to EC and CPU UART ports, for convenient debugging,
 * Reflashing of EC and system firmware (recovery of bricked systems).

For example, it can act as a USB host to simulate connection and
removal of external USB devices. It also provides JTAG/SWD support.

The raiden_debug programmer supports:

 * Servo v4,
 * Servo micro,
 * suzy-q CCD debug cable.

The Servo v2 is actually supported by the ft2232 programmer driver.

While it isn't ideal to have usb_device.[h|c] when usbdev.c already
exists in-tree, we get the initial raiden_debug supporting code in so
we can massage it moving forwards.

Squash in,
  usb_device: needed for raiden_debug prog

BUG=b:143389556
BRANCH=none
TEST=builds && ran `./flashrom -p raiden_debug --flash-name` && `-r`.

Change-Id: Ifad273a708acea4de797a0808be58960635a8864
Signed-off-by: Edward O'Callaghan <quasisec@google.com>
---
M Makefile
M flashrom.c
M meson.build
M meson_options.txt
M programmer.h
A raiden_debug_spi.c
A usb_device.c
A usb_device.h
8 files changed, 977 insertions(+), 0 deletions(-)