poppy: add detachbase and attachbase uart console commands
poppy: add detachbase and attachbase uart console commands

This patch adds two commands to simulate detachbase and
attachbase uart console commands to test & debug automation.

BRANCH=none
BUG=b:37223093
TEST=attach or detach base and check if event is generated

Change-Id: Ie4a487ebd8929f0584da0b59c094f9d9aff13fb7
Signed-off-by: Subramony Sesha <d1a9f30762802c72f0f615cdffe1157dbe58a2b3@intel.com>
Signed-off-by: Archana Patni <41ae10a59316ee0595374b540cf8e1108afaed3a@intel.com>
Signed-off-by: Jenny TC <69498ef46fb20cbbe7d8a1d7bc07f9711dcaf0b6@intel.com>
Reviewed-on: https://chromium-review.googlesource.com/486521
Commit-Ready: Jenny Tc <69498ef46fb20cbbe7d8a1d7bc07f9711dcaf0b6@intel.corp-partner.google.com>
Tested-by: Jenny Tc <69498ef46fb20cbbe7d8a1d7bc07f9711dcaf0b6@intel.corp-partner.google.com>
Reviewed-by: Furquan Shaikh <6be5c96c464778f89679b1062a2e0a6af93d2aa5@chromium.org>
Reviewed-by: Nicolas Boichat <f3daba1cdc403799935674d3cd4b0e5bd1804232@chromium.org>

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