spd: Move SPD read from flashrom to common lib

Move the duplicate code to common lib.

BUG=None
TEST=merge mosys

Change-Id: I7c54942ad28ebc47f62df05743341e2c51a25489
Signed-off-by: Eric Lai <ericr_lai@compal.corp-partner.google.com>
Reviewed-on: https://chromium-review.googlesource.com/1880911
Tested-by: EricR Lai <ericr_lai@compal.corp-partner.google.com>
Tested-by: David Burger <dburger@chromium.org>
Commit-Ready: Jack Rosenthal <jrosenth@chromium.org>
Legacy-Commit-Queue: Commit Bot <commit-bot@chromium.org>
Reviewed-by: Jack Rosenthal <jrosenth@chromium.org>
27 files changed