Adds a new HOOK_TICK event which is called every 250ms (LM4) or 500ms
(STM32). This will be used to consolidate a number of tasks which do
small amounts of work infrequently, and previously needed their own
task functions.
This CL adds the tick task; subsequent CLs will consolidate watchdog
and other tasks into tick hooks.
BUG=chrome-os-partner:15714
BRANCH=none
TEST=taskinfo shows TICK task as lowest priority
Change-Id: I9068ee99d56a5bf5c12afd86ad51998c013f4954
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/36908
Reviewed-by: Simon Glass <sjg@chromium.org>
4a0b4262d3