RDMA/ocrdma: Simplify process_mad function

Change the switch with one case into a simple if statement so the code is
less confusing.

Link: https://lore.kernel.org/r/20191029062745.7932-12-leon@kernel.orgSigned-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/hw/ocrdma/ocrdma_ah.c

@@ -256,20 +256,16 @@ int ocrdma_process_mad(struct ib_device *ibdev,
 		       struct ib_mad_hdr *out, size_t *out_mad_size,
 		       u16 *out_mad_pkey_index)
 {
-	int status;
+	int status = IB_MAD_RESULT_SUCCESS;
 	struct ocrdma_dev *dev;
 	const struct ib_mad *in_mad = (const struct ib_mad *)in;
 	struct ib_mad *out_mad = (struct ib_mad *)out;
 
-	switch (in_mad->mad_hdr.mgmt_class) {
-	case IB_MGMT_CLASS_PERF_MGMT:
+	if (in_mad->mad_hdr.mgmt_class == IB_MGMT_CLASS_PERF_MGMT) {
 		dev = get_ocrdma_dev(ibdev);
 		ocrdma_pma_counters(dev, out_mad);
-		status = IB_MAD_RESULT_SUCCESS | IB_MAD_RESULT_REPLY;
-		break;
-	default:
-		status = IB_MAD_RESULT_SUCCESS;
-		break;
+		status |= IB_MAD_RESULT_REPLY;
 	}
+
 	return status;
 }