512 bytes isn't enough to capture all the debug output early in the
init process, and Link EC has lots of unused RAM. stm32 doesn't, so
only do this for LM4 processor.
BUG=none
TEST=build; debug output during init shouldn't be garbled
Change-Id: Ie4fd204fa4e0c6ca99ea7eae94b095ef175836e4
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/26877