RDMA/hns: Fix type of sq_signal_bits

This bit should be in type of enum ib_sig_type, or there will be a sparse
warning.

Fixes: bfe860351e ("RDMA/hns: Fix cast from or to restricted __le32 for driver")
Link: https://lore.kernel.org/r/1612517974-31867-3-git-send-email-liweihang@huawei.com
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Weihang Li <liweihang@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

drivers/infiniband/hw/hns/hns_roce_device.h

@@ -661,7 +661,7 @@ struct hns_roce_qp {
 	struct hns_roce_db	sdb;
 	unsigned long		en_flags;
 	u32			doorbell_qpn;
-	u32			sq_signal_bits;
+	enum ib_sig_type	sq_signal_bits;
 	struct hns_roce_wq	sq;
 
 	struct hns_roce_mtr	mtr;