multi: ensure addresses are no longer assumed to be TCP addresses only

In this commit, we go through the codebase looking for TCP address
assumptions and modifying them to include the recently introduced onion
addresses. This enables us to fully support onion addresses within the
daemon.

discovery/bootstrapper.go

@@ -165,12 +165,12 @@ func (c *ChannelGraphBootstrapper) SampleNodeAddrs(numAddrs uint32,
 				// If we haven't yet reached our limit, then
 				// we'll copy over the details of this node
 				// into the set of addresses to be returned.
-				tcpAddr, ok := nodeAddr.(*net.TCPAddr)
-				if !ok {
-					// If this isn't a valid TCP address,
-					// then we'll ignore it as currently
-					// we'll only attempt to connect out to
-					// TCP peers.
+				switch nodeAddr.(type) {
+				case *net.TCPAddr, *tor.OnionAddr:
+				default:
+					// If this isn't a valid address
+					// supported by the protocol, then we'll
+					// skip this node.
 					return nil
 				}
 
@@ -179,7 +179,7 @@ func (c *ChannelGraphBootstrapper) SampleNodeAddrs(numAddrs uint32,
 				// error.
 				a = append(a, &lnwire.NetAddress{
 					IdentityKey: node.PubKey(),
-					Address:     tcpAddr,
+					Address:     nodeAddr,
 				})
 			}