Add support for the DP83822 TI PHYs which are assembled on a F614N sidecard.

On the new F614N sidecard, which is exclusively attached to the new F26L23 CPU module, DP83822 PHYs from TI are used. In contrast to those DP83822 PHYs used on the F301N module, we have to configure the link and the activity LED here.

LED0 is configured via the extended register @ 0x0025 as activity indicator, while LED1 is configured via the extended registers @ 0x0460 and 0x0462 as link indicator.

To stay backward compatible, the new module parameter "platform" is introduced. If this parameter is set to "F026L23" and the PHY Identifier Register #1 is equal to the DP83822's ID "0x2000", the new LED behavior is configured.

Note: We also did some minor code beautification (indentation, tabs, etc.) and some minor doc updates.