usb: pd: policy_engine: Add support to handle floating charger

There is a possibility of PMI detecting SDP as a floating charger
when connected to a PC. Workaround this issue by starting peripheral
stack for floating charger as well. Stop peripheral stack after 10 sec
in absence of USB device enumeration.

Change-Id: I6effee71affbe0baeb28c54ce799ade79ec4b42a
Signed-off-by: Hemant Kumar <hemantk@codeaurora.org>