Add the ability to disable Link-Local answer

pion/ice doesn't gather Link-Local addresses, these answers break
connectivity

config.go

@@ -41,6 +41,9 @@ type Config struct {
 	// IncludeLoopback will include loopback interfaces to be eligble for queries and answers.
 	IncludeLoopback bool
 
+	// DisableLinkLocal disables answering with the Link-Local Address
+	DisableLinkLocal bool
+
 	// Interfaces will override the interfaces used for queries and answers.
 	Interfaces []net.Interface
 }

conn.go

@@ -877,6 +877,10 @@ func (c *Conn) readLoop(name string, pktConn ipPacketConn, inboundBufferSize int
 										continue
 									}
 
+									if config.DisableLinkLocal && ipCopy.IsLinkLocalUnicast() {
+										continue
+									}
+
 									selectedIP = ipCopy
 									break
 								}