mscc.c: Add support for additional VSC PHYs

Add support for the following VSC PHYs
	VSC8504, VSC8552, VSC8572
	VSC8562, VSC8564, VSC8575, VSC8582

Updates for v2:
	Checked for NULL on input to container_of
	Changed a large if else series to a switch statement.
	Added a WARN_ON to make sure lowest nibble of mask is 0

Signed-off-by: Bryan Whitehead <Bryan.Whitehead@microchip.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>