RDMA/qedr: Fix error return code in qedr_iw_connect()

Fix to return a negative error code from the error handling case instead
of 0, as done elsewhere in this function.

Fixes: 82af6d19

 ("RDMA/qedr: Fix synchronization methods and memory leaks in qedr")
Link: https://lore.kernel.org/r/20210408113135.92165-1-wangwensheng4@huawei.com
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Wensheng <wangwensheng4@huawei.com>
Acked-by: Michal <Kalderon &lt;michal.kalderon@marvell.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>