net: ti: cpmac: Fix build error due to missed API change

Commit 7f854420 ("phy: Add API for {un}registering an mdio device to
a bus") introduces an API to access mii_bus structures, but missed to
update the TI cpamc driver. This results in the following error message.

drivers/net/ethernet/ti/cpmac.c: In function 'cpmac_probe':
drivers/net/ethernet/ti/cpmac.c:1119:18: error:
	'struct mii_bus' has no member named 'phy_map'

Fixes: 7f854420

 ("phy: Add API for {un}registering an mdio device to a bus")
Cc: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>