rxrpc: Fix some minor issues with bundle tracing

Fix some superficial issues with the tracing of rxrpc_bundle structs,
including:

 (1) Set the debug_id when the bundle is allocated rather than when it is
     set up so that the "NEW" trace line displays the correct bundle ID.

 (2) Show the refcount when emitting the "FREE" traceline.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: linux-afs@lists.infradead.org
cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>