pit: update I2C4 speed constant

BUG=none
BRANCH=none
TEST=tested on pit

Change-Id: I61896f70f41eec12a1499307f695fa69f3d42d88
Reviewed-on: https://gerrit.chromium.org/gerrit/59692
Reviewed-by: Gabe Black <gabeblack@chromium.org>
Commit-Queue: David Hendricks <dhendrix@chromium.org>
Tested-by: David Hendricks <dhendrix@chromium.org>
1 file changed