net: phy: broadcom: Add genphy_suspend and genphy_resume for BCM5464

This puts the quad PHY ports in power-down mode when the PHY transitions
to the PHY_HALTED state.  It is likely that all the other PHYs support
the BMCR_PDOWN bit, but I only have the BCM5464R to test.

Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/broadcom.c

@@ -663,6 +663,8 @@ static struct phy_driver broadcom_drivers[] = {
 	.config_init	= bcm54xx_config_init,
 	.ack_interrupt	= bcm_phy_ack_intr,
 	.config_intr	= bcm_phy_config_intr,
+	.suspend	= genphy_suspend,
+	.resume		= genphy_resume,
 }, {
 	.phy_id		= PHY_ID_BCM5481,
 	.phy_id_mask	= 0xfffffff0,