linux-imx

staging: mt7621-pci-phy: update bindings documentation

Device tree has been simplified to use phy-cells instead of
using child nodes. Update documentation accordly.

Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Reviewed-by: NeilBrown <neil@brown.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>