RDMA/nes: Change MDIO bus clock to 2.5MHz

Change the PHY clock divisor to make the MDIO clock 2.5MHz, instead of
3.5MHz (which is out of spec).

Signed-off-by: Tatyana Nikolova <Tatyana.E.Nikolova@intel.com>
Signed-off-by: Faisal Latif <Faisal.Latif@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

drivers/infiniband/hw/nes/nes_hw.c

@@ -1529,7 +1529,7 @@ int nes_init_phy(struct nes_device *nesdev)
 	} else {
 		/* setup 10G MDIO operation */
 		tx_config &= 0xFFFFFFE3;
-		tx_config |= 0x15;
+		tx_config |= 0x1D;
 	}
 	nes_write_indexed(nesdev, NES_IDX_MAC_TX_CONFIG, tx_config);