RDMA/core: Get xmit slave for LAG

Add a call to rdma_lag_get_ah_roce_slave() when the address handle is
created. Lower driver can use it to select the QP's affinity port.

Link: https://lore.kernel.org/r/20200430192146.12863-15-maorg@mellanox.com
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index e6c18ec..8d29f2f 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -883,6 +883,7 @@ __attribute_const__ enum ib_rate mult_to_ib_rate(int mult);
 struct rdma_ah_init_attr {
 	struct rdma_ah_attr *ah_attr;
 	u32 flags;
+	struct net_device *xmit_slave;
 };
 
 enum rdma_ah_attr_type {
@@ -1272,6 +1273,7 @@ struct ib_qp_attr {
 	u8			alt_port_num;
 	u8			alt_timeout;
 	u32			rate_limit;
+	struct net_device	*xmit_slave;
 };
 
 enum ib_wr_opcode {