volteer: Enable CONFIG_DEBUG_ASSERT_BRIEF
volteer: Enable CONFIG_DEBUG_ASSERT_BRIEF

Enable CONFIG_DEBUG_ASSERT_BRIEF to reduce image size. This saves 2368
bytes in RO and 2392 bytes in RW.

Current free space: 2592 RO, 2608 RW

BUG=none
BRANCH=firmware-volteer-13521.B-master
TEST=make buildall

Signed-off-by: Keith Short <f6d578f97033c25f1206cb57d52f358974c82954@chromium.org>
Change-Id: If71acd83ad26a07e7277aadffaeedf4724364f4c
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2569851
Reviewed-by: Abe Levkoy <2e1ad7039298f93262cf06bbb457275fb3e2ecb5@chromium.org>
Commit-Queue: Abe Levkoy <2e1ad7039298f93262cf06bbb457275fb3e2ecb5@chromium.org>

coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec