RDMA/bnxt_re: Fix error return code in bnxt_qplib_cq_process_terminal()

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

Fixes: 1ac5a404

 ("RDMA/bnxt_re: Add bnxt_re RoCE driver")
Link: https://lore.kernel.org/r/20210408113137.97202-1-wangwensheng4@huawei.com
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Wensheng <wangwensheng4@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>