test: set P2PConnection.p2p_connected_to_node in peer_connect_helper()

Set `P2PConnection.p2p_connected_to_node` in
`P2PConnection.peer_connect_helper()` instead of
`TestNode.add_p2p_connection()` and
`TestNode.add_outbound_p2p_connection()`.

This way tests can create an instance of `P2PConnection` and use
`P2PConnection.peer_connect_helper()` directly.

test/functional/test_framework/p2p.py

@@ -188,6 +188,7 @@ class P2PConnection(asyncio.Protocol):
         self.on_connection_send_msg = None
         self.recvbuf = b""
         self.magic_bytes = MAGIC_BYTES[net]
+        self.p2p_connected_to_node = dstport != 0
 
     def peer_connect(self, dstaddr, dstport, *, net, timeout_factor, supports_v2_p2p):
         self.peer_connect_helper(dstaddr, dstport, net, timeout_factor)

test/functional/test_framework/test_node.py

@@ -714,7 +714,6 @@ class TestNode():
         if supports_v2_p2p is None:
             supports_v2_p2p = self.use_v2transport
 
-        p2p_conn.p2p_connected_to_node = True
         if self.use_v2transport:
             kwargs['services'] = kwargs.get('services', P2P_SERVICES) | NODE_P2P_V2
         supports_v2_p2p = self.use_v2transport and supports_v2_p2p
@@ -781,7 +780,6 @@ class TestNode():
             self.log.debug("Connecting to %s:%d %s" % (address, port, connection_type))
             self.addconnection('%s:%d' % (address, port), connection_type, advertise_v2_p2p)
 
-        p2p_conn.p2p_connected_to_node = False
         if supports_v2_p2p is None:
             supports_v2_p2p = self.use_v2transport
         if advertise_v2_p2p is None: