Load balancer and link discovery compile errors fixed

src/main/java/net/floodlightcontroller/core/IOFSwitch.java

src/main/java/net/floodlightcontroller/core/OFSwitch.java

...et/floodlightcontroller/linkdiscovery/ILinkDiscovery.java

...ntroller/linkdiscovery/internal/LinkDiscoveryManager.java

...ain/java/net/floodlightcontroller/loadbalancer/LBVip.java

...a/net/floodlightcontroller/loadbalancer/LoadBalancer.java

...java/net/floodlightcontroller/routing/ForwardingBase.java