It was agreed that phy-connection-type was a better name for
the interface-type property, so this patch renames it.

Also, the max-speed property name was determined too generic,
and is therefore eliminated in favour of phy-connection-type
derivation logic.

includes corrections to copyright text.
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>