rxrpc: Check that the client conns cache is empty before module removal

Check that the client conns cache is empty before module removal and bug if
not, listing any offending connections that are still present.  Unfortunately,
if there are connections still around, then the transport socket is still
unexpectedly open and active, so we can't just unallocate the connections.

Signed-off-by: David Howells <dhowells@redhat.com>
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 3f0d047..6583a83 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -541,6 +541,7 @@
 
 int rxrpc_get_client_connection_id(struct rxrpc_connection *, gfp_t);
 void rxrpc_put_client_connection_id(struct rxrpc_connection *);
+void rxrpc_destroy_client_conn_ids(void);
 
 /*
  * conn_event.c