intel/common: compress VBT

It's pretty well compressible which helps when space is tight.
The code encodes the assumption that the VBT is 8kb or less. Haven't
seen a larger one yet.

BUG=b:77971803,b:78541692
TEST=build, see that vbt.bin is compressed, boot, check log that the
reported VBT size is correct.

Change-Id: Ie25bca21d9edc408f441a292bbe2ab0459948ec4
Signed-off-by: Patrick Georgi <pgeorgi@google.com>
Reviewed-on: https://review.coreboot.org/25927
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2 files changed