docs: Cleanup of Design Doc
docs: Cleanup of Design Doc

The google-drive -> markdown added those reference points and they are
not needed and show up.  This removes them.

Change-Id: If7ab88a08b048e78b4cd8a2159e7e56180bd55a3
Signed-off-by: Patrick Venture <36c53fa43f47f3fd67cb2fc38031827244d18a1f@google.com>

openbmc/phosphor-pid-control,openbmc/phosphor-pid-control