broadwell: Enable double self refresh by default

Rather than enable this in every mainboard just enable
it by default for all broadwell devices and let a
specific mainboard disable it if needed.

BUG=chrome-os-partner:34420
BRANCH=samus,auron
TEST=build and boot on samus

Change-Id: I26d9f2e2a12d3f2f888ecb5af0d949eec5928f57
Signed-off-by: Duncan Laurie <dlaurie@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/238400
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
1 file changed