Fix vulnerabilities and bugs in policy/engine

Code fixes for 1 bug and 17 vulnerabilities reported by Sonar in
policy/engine

Change-Id: I7b641795c790ec15418bd9ae3a414279e1b0f733
Issue-ID: POLICY-662
Signed-off-by: eramkve <ram.krishna.verma@ericsson.com>
11 files changed