[BUG] fix target.hostname of links

Before this commit, the value of target.hostname was incorrect.
It was accidentially pointing to the hostname of the source of
the link. This means target.hostname was equal to source.hostname.

Fixes: #197
Fixes: 0325aad
PR: #200

runtime/nodes.go

@@ -117,7 +117,7 @@ func (nodes *Nodes) NodeLinks(node *Node) (result []Link) {
 	for sourceMAC, batadv := range neighbours.Batadv {
 		for neighbourMAC, link := range batadv.Neighbours {
 			if neighbourID := nodes.ifaceToNodeID[neighbourMAC]; neighbourID != "" {
-				neighbour := nodes.List[neighbours.NodeID]
+				neighbour := nodes.List[neighbourID]
 
 				link := Link{
 					SourceID:      neighbours.NodeID,
@@ -128,10 +128,10 @@ func (nodes *Nodes) NodeLinks(node *Node) (result []Link) {
 				}
 
 				if neighbour.Nodeinfo != nil {
-					link.SourceHostname = neighbour.Nodeinfo.Hostname
+					link.TargetHostname = neighbour.Nodeinfo.Hostname
 				}
 				if node.Nodeinfo != nil {
-					link.TargetHostname = node.Nodeinfo.Hostname
+					link.SourceHostname = node.Nodeinfo.Hostname
 				}
 
 				result = append(result, link)