Instead of playing mount and loop device games, this change adds support for
update_bootloaders.sh to directly update the EFI system partition living in the
image if a file, offset, and size is supplied.
TEST=build_image for x86-generic; booted resulting image
BUG=broken build
Change-Id: I3d891fd965df6fb4abfc63d660e314c497a4184d
Review URL: http://codereview.chromium.org/3006006
Right now, the created arm.mbr is the size of the ESP
partition. It should be truncated though to just the mbr size.
In addition, dm= doesnt do anything on arm yet so replacing use with a todo and adding a check if it isn't there.
TEST=manually ran
BUG=none
TBR=fes
Adds two helpers that are not used yet. They will be
used in the next CL to unify the bootloaders in use
in build_image.
TEST=used in the next CL but otherwise not called.
BUG=chromium-os:327
Review URL: http://codereview.chromium.org/2829039