ARM: dts: Add ethernet to a bunch of platforms

These platforms have the PHY defined already so we just
need to add a single device node to each of them to activate
the ethernet device.

The PHY skew/delay settings for pin control is known from a
few vendor trees and old OpenWRT patch sets.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>