On flow being removed from switch on idle timeout, onFlowRemoved() api was
invoked and while conversion reason was not being converted and added, so
the application using API onFlowRemoved() was not getting the reason for
flow being removed from the switch.
This change will provide the reason invoking onFlowRemoved() API
Change-Id: Id8b957b5b2cc581215fb84b8ca84d1d9a04e5619
Signed-off-by: eeiillu <suja.t@ericsson.com>