Fix minor bug in FRM proactive flow code path

ISSUE:
When proactive flows are installed on a switch
(as a result of user configuring the forwarding mode of the node to proactive)
in case switch fails to install any of these flows, the informational log still
reports that the proactive flow was succesfully installed.
CHANGE:
When calling addStaticFlowInternal() make sure to pass the restore flag as false

Change-Id: I7f1e85d40624a145c6d71bb1149b14c825894312
Signed-off-by: Alessandro Boch <aboch@cisco.com>