dsa: Replace mii_bus with a generic host device

This change makes it so that instead of passing and storing a mii_bus we
instead pass and store a host_dev.  From there we can test to determine the
exact type of device, and can verify it is the correct device for our switch.

So for example it would be possible to pass a device pointer from a pci_dev
and instead of checking for a PHY ID we could check for a vendor and/or device
ID.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/mv88e6131.c

@@ -22,10 +22,14 @@
 #define ID_6095		0x0950
 #define ID_6131		0x1060
 
-static char *mv88e6131_probe(struct mii_bus *bus, int sw_addr)
+static char *mv88e6131_probe(struct device *host_dev, int sw_addr)
 {
+	struct mii_bus *bus = dsa_host_dev_to_mii_bus(host_dev);
 	int ret;
 
+	if (bus == NULL)
+		return NULL;
+
 	ret = __mv88e6xxx_reg_read(bus, sw_addr, REG_PORT(0), 0x03);
 	if (ret >= 0) {
 		ret &= 0xfff0;