FRM should not remove a static flow config on async error report

FRM should not remove a static flow config on async error report

- Currently FRM is removing the affected static flow config on
  receiving a flow error event from the switch.
  The correct action is to modify the config status.
  The config removal was a temporary fix for the flow configuration across
  cluster (request served by another controller node) when this request was
  always sent asynchronously. Now it is no longer needed as FRM implements
  both the synch and async flow rewust across the cluster.

Change-Id: If2d473cd4688bdf83ecc0a0f5eb210b938157d29
Signed-off-by: Alessandro Boch <aboch@cisco.com>