RDMA/netlink: Implement counter dumpit calback

This patch adds the ability to return all available counters together with
their properties and hwstats.

Signed-off-by: Mark Zhang <markz@mellanox.com>
Reviewed-by: Majd Dibbiny <majd@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

include/rdma/rdma_counter.h

@@ -37,6 +37,7 @@ struct rdma_counter {
 	struct kref			kref;
 	struct rdma_counter_mode	mode;
 	struct mutex			lock;
+	struct rdma_hw_stats		*stats;
 	u8				port;
 };
 
@@ -47,4 +48,6 @@ int rdma_counter_set_auto_mode(struct ib_device *dev, u8 port,
 int rdma_counter_bind_qp_auto(struct ib_qp *qp, u8 port);
 int rdma_counter_unbind_qp(struct ib_qp *qp, bool force);
 
+int rdma_counter_query_stats(struct rdma_counter *counter);
+
 #endif /* _RDMA_COUNTER_H_ */