bgpmap: fix regexp to match interface names with non-alphanumerical characters

Commit eaf531eee2 ("Correctly parse aspath for both bird 1.x and 2.0.")
inadvertently made a regexp more strict, and it no longer matches some
interface names.  Example include `eth1.945` (tagged VLAN, which is a
common use-case for routers) or `br-foo`.

As a result, the regexp would not parse the "peer protocol name" that is
normally displayed on the bgpmap.

Fixes: #64

lg.py

@@ -568,7 +568,7 @@ def build_as_tree_from_raw_bird_ouput(host, proto, text):
                 net_dest = expr.group(1).strip()
             peer_protocol_name = expr.group(2).strip()
 
-        expr2 = re.search(r'(.*)via\s+([0-9a-fA-F:\.]+)\s+on\s+\w+(\s+\[(\w+)\s+)?', line)
+        expr2 = re.search(r'(.*)via\s+([0-9a-fA-F:\.]+)\s+on\s+\S+(\s+\[(\w+)\s+)?', line)
         if expr2:
             if path:
                 path.append(net_dest)