futility: handle truncated BIOS images without segfault

A truncated BIOS with an otherwise valid FMAP that now points way
off the end of the file shouldn't cause coredumps.

BUG=none
BRANCH=ToT
TEST=make runtests

Change-Id: Idf96e1e6a381bf0fe0b1cb2d16e3dad39ce7a0dc
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/245500
Reviewed-by: Randall Spangler <rspangler@chromium.org>
6 files changed