RDMA/mlx5: Clear old rate limit when closing QP

RDMA/mlx5: Clear old rate limit when closing QP

Before QP is closed it changes to ERROR state, when this happens
the QP was left with old rate limit that was already removed from
the table.

Fixes: f867ab3f5827 ("IB/mlx5: Properly adjust rate limit on QP state transitions")
Signed-off-by: Rafi Wiener <rafiw@mellanox.com>
Signed-off-by: Oleg Kuporosov <olegk@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Link: https://lore.kernel.org/r/20191002120243.16971-1-leon@kernel.org
Signed-off-by: Doug Ledford <dledford@redhat.com>