FALCO: stop using the slippy graphics code

It's time to start cleaning up the falco graphics code, but it needs
to have its own files, not slippy's.

Change-Id: I7dbe27eafbf247b5c7806819bf0059d8b10e842c
Signed-off-by: Ronald G. Minnich <rminnich@google.com>
Reviewed-on: https://chromium-review.googlesource.com/172501
Tested-by: Ronald Minnich <rminnich@chromium.org>
Reviewed-by: Stefan Reinauer <reinauer@google.com>
Commit-Queue: David Hendricks <dhendrix@chromium.org>
(cherry picked from commit 262a0c16a39871d14972a92bff2dbc24de2ca3f0)
Signed-off-by: Isaac Christensen <isaac.christensen@se-eng.com>
Reviewed-on: http://review.coreboot.org/6832
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>