cbfs: don't load x86 programs over the top of read-only media

On x86 the early stages are currently execute-in-place which
means they live in the memory-mapped spi flash. However, when
loading romstage from verstage the romstage is
execute-in-place so it's unnecessary to write over a read-only
media -- not to mention writing to read-only memory is wrong
to begin with.

BUG=chrome-os-partner:44827
BRANCH=None
TEST=Built and booted glados. Noted reduction of 20ms when
     loading romstage.

Change-Id: I7cd399302a3925a05fbce82600b4c50ea66a0fcb
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/11823
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

0 files changed, 0 insertions, 0 deletions