It's only board-specific in that we've only needed it on snow so far.
But by that logic, x86_power would be board specific because we've
only needed it on link.
No functionality change, just moving code between files and renaming
the interface to indicate it's not board-specific.
BUG=chrome-os-partner:18343
BRANCH=none
TEST=build daisy,snow,spring
Change-Id: I35debdaa71829d55a2fbc5d3c62b2aaf6e467633
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/45879
