rxe: fix error completion wr_id and qp_num

Error completions must still contain a valid wr_id and
qp_num such that the consumer can rely on. Correctly
fill these fields in receive error completions.

Reported-by: Walker Benjamin <benjamin.walker@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Zhu Yanjun <yanjun.zhu@oracle.com>
Tested-by: Zhu Yanjun <yanjun.zhu@oracle.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>