board/zinger: Disable CONFIG_DEBUG_PRINTF
board/zinger: Disable CONFIG_DEBUG_PRINTF

We're getting low on RO flash space, so disable CONFIG_DEBUG_PRINTF to
free up more space.

BRANCH=none
BUG=b:172020503
TEST=make buildall

Signed-off-by: Tom Hughes <fc5c12f30a5ed2baa0581f44ee14ad1eb7b20d83@chromium.org>
Change-Id: I44345f076d26b8aab111f01081fe9bdfd0a69dee
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3253649
Reviewed-by: Edward Hill <db1406b34e091703092b6b136bdfeb2c8125fc0e@chromium.org>

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