soc: qcom: dfc: ignore indications during RAT switch

Added support to identify the start and end of RAT switch from
QMI DFC indications. Any additional messages in between will be
ignored. This is to resolve a race condition that could happen
if QMI messages are coming from different transports.

Change-Id: I3bb28a34348509eae54d30958555cf1d207838c7
Acked-by: Weiyi Chen <weiyic@qti.qualcomm.com>
Signed-off-by: Sean Tranchetti <stranche@codeaurora.org>