RDMA/rxe: Fix mw bind to allow any consumer key portion

The current implementation of rxe_check_bind_mw() in rxe_mw.c is incorrect
since it requires the new key portion provided by the mw consumer to be
different than the previous key portion. This is not required by the
IBA. Remove the test.

Link: https://lore.kernel.org/linux-rdma/fb4614e7-4cac-0dc7-3ef7-766dfd10e8f2@gmail.com/
Fixes: 32a577b4 ("Add support for bind MW work requests")
Link: https://lore.kernel.org/r/20220714204619.13396-1-rpearsonhpe@gmail.comSigned-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

drivers/infiniband/sw/rxe/rxe_mw.c

@@ -50,8 +50,6 @@ int rxe_dealloc_mw(struct ib_mw *ibmw)
 static int rxe_check_bind_mw(struct rxe_qp *qp, struct rxe_send_wqe *wqe,
 			 struct rxe_mw *mw, struct rxe_mr *mr)
 {
-	u32 key = wqe->wr.wr.mw.rkey & 0xff;
-
 	if (mw->ibmw.type == IB_MW_TYPE_1) {
 		if (unlikely(mw->state != RXE_MW_STATE_VALID)) {
 			pr_err_once(
@@ -89,11 +87,6 @@ static int rxe_check_bind_mw(struct rxe_qp *qp, struct rxe_send_wqe *wqe,
 		}
 	}
 
-	if (unlikely(key == (mw->rkey & 0xff))) {
-		pr_err_once("attempt to bind MW with same key\n");
-		return -EINVAL;
-	}
-
 	/* remaining checks only apply to a nonzero MR */
 	if (!mr)
 		return 0;