Merge branch 'macb-ethtool-ringparam'

Zach Brown says:

====================
macb: Add ethtool get_ringparam and set_ringparam to cadence

There are use cases like RT that would benefit from being able to tune the
macb rx/tx ring sizes. The ethtool set_ringparam function is the standard way
of doing so.

The first patch changes the hardcoded tx/rx ring sizes to variables that are
set to a hardcoded default.

The second patch implements the get_ringparam and set_ringparam fucntions.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/cadence/macb.h

@@ -811,6 +811,9 @@ struct macb {
 	void			*rx_buffers;
 	size_t			rx_buffer_size;
 
+	unsigned int		rx_ring_size;
+	unsigned int		tx_ring_size;
+
 	unsigned int		num_queues;
 	unsigned int		queue_mask;
 	struct macb_queue	queues[MACB_MAX_QUEUES];