IB/uverbs: Introduce RWQ Indirection table

User applications that want to spread traffic on several WQs, need to
create an indirection table, by using already created WQs.

Adding uverbs API in order to create and destroy this table.

Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Matan Barak <matanb@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Doug Ledford <dledford@redhat.com>

include/rdma/ib_verbs.h

@@ -1326,6 +1326,7 @@ struct ib_ucontext {
 	struct list_head	xrcd_list;
 	struct list_head	rule_list;
 	struct list_head	wq_list;
+	struct list_head	rwq_ind_tbl_list;
 	int			closing;
 
 	struct pid             *tgid;