phy: micrel: Add definitions for common Micrel PHY registers

Add defines for common Micrel PHY setups so that other platforms
can use them. Update imx61 and sama5 hardware to use the micrel_phy.h
PHY defines.

Also add support for the KSZ9021RLRN PHY.

Signed-off-by: Dinh Nguyen <dinguyen@altera.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: David S. Miller <davem@davemloft.net>
CC: Andrew Victor <linux@maxim.org.za>
CC: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: netdev@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>