Cr50: Delay sleeping for longer after console input
Cr50: Delay sleeping for longer after console input

Wait at least 10 seconds after the last console input before
invoking sleep or deep sleep.

BUG=chrome-os-partner:49955, chrome-os-partner:50721
BRANCH=none
TEST=make buildall; test on Cr50

Use the "idle d" console command to put the Cr50 into deep sleep
when idle (refer to previous commit messages for the setup
required).

Wake it up, then let it sleep again. It should go back to sleep
quickly when woken via USB, but should take much longer when
awakened by typing on the serial console.

Signed-off-by: Bill Richardson <129945214b1d548d8e49b6c29c43094f8c78057f@chromium.org>
Change-Id: I7a2b840565f5d82e0dbdf8a3e75061a69cb9e405
Reviewed-on: https://chromium-review.googlesource.com/336835
Reviewed-by: Dominic Rizzo <a9e5fb9a80871b4edba0a94343af83678d394845@google.com>

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