RDMA/rtrs-clt: Start hb after path_up

If we start hb too early, it will confuse server side to close
the session.

Fixes: 6a98d71d

 ("RDMA/rtrs: client: main functionality")
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Reviewed-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Grzegorz Prajsner <grzegorz.prajsner@ionos.com>
Link: https://lore.kernel.org/r/20231120154146.920486-3-haris.iqbal@ionos.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>