This imports the new cache maintenance API from coreboot at
commit bba8090. This is a BSD-licensed implementation which
exposes cache maintenance opertaions necessary for payloads
for things such as DMA transfers.
Change-Id: I554676db89517bebc6edae4f7ab7e5882e6f986d
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Reviewed-on: http://review.coreboot.org/2974
Tested-by: build bot (Jenkins)
David Hendricks