util/intelvbttool: Cleanup and fixes

* Clear remalloced memory
* Fix check for invalid VBT offset in header
* Fix VBIOS checksum generation
* Fix VBIOS size field
* Align VBIOS size to multiple of 512
* Reassign pointers after use of remalloc
* Don't leak on error path

Current version is enough to allow the proprietary Windows Intel GMA
driver to find the VBT in the legacy VBIOS area and it doesn't BSOD
any more.

The LVDS screen remains black, due to an unknown issue with the
proprietary driver, while the VGA works.

Tested with libgfxinit and native graphics init.

Change-Id: If07b1bb51d8fb3499d13102f70fedb36c020fb72
Signed-off-by: Patrick Rudolph <siro@das-labor.org>
Reviewed-on: https://review.coreboot.org/29099
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

0 files changed, 0 insertions, 0 deletions