RDMA/ocrdma: Suppress gcc 7 fall-through complaints

Avoid that gcc 7 reports the following warning when building with
W=1:

warning: this statement may fall through [-Wimplicit-fallthrough=]
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Selvin Xavier <selvin.xavier@broadcom.com>
Cc: Devesh Sharma <devesh.sharma@broadcom.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/ocrdma/ocrdma_verbs.c

@@ -2247,6 +2247,7 @@ int ocrdma_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr,
 		case IB_WR_SEND_WITH_IMM:
 			hdr->cw |= (OCRDMA_FLAG_IMM << OCRDMA_WQE_FLAGS_SHIFT);
 			hdr->immdt = ntohl(wr->ex.imm_data);
+			/* fall through */
 		case IB_WR_SEND:
 			hdr->cw |= (OCRDMA_SEND << OCRDMA_WQE_OPCODE_SHIFT);
 			ocrdma_build_send(qp, hdr, wr);
@@ -2260,6 +2261,7 @@ int ocrdma_post_send(struct ib_qp *ibqp, struct ib_send_wr *wr,
 		case IB_WR_RDMA_WRITE_WITH_IMM:
 			hdr->cw |= (OCRDMA_FLAG_IMM << OCRDMA_WQE_FLAGS_SHIFT);
 			hdr->immdt = ntohl(wr->ex.imm_data);
+			/* fall through */
 		case IB_WR_RDMA_WRITE:
 			hdr->cw |= (OCRDMA_WRITE << OCRDMA_WQE_OPCODE_SHIFT);
 			status = ocrdma_build_write(qp, hdr, wr);