Wake-On-LAN and VIA Rhine / DFE-530TX

I have added some code for Wake-On-LAN support in via-rhine.c which basically boils down to handling the WOL cases in via_rhine_ethtool_ioctl().

There are two pitfalls to consider:

- Depending on the version of the chip, the bit flags are in different locations, and not all chips support the same WOL options. We already have chip specific code paths, hence no problem.

- The manual I have for the Rhine-based D-Link DFE-530TX claims WOL support, and these cards come indeed with a WOL connector. That doesn't mean WOL works, though. The DFE-530TX exists in different revisions (sticker on the board): wrong revision -> no WOL. The LK Rhine driver does not read stickers, so the problem is right there.

With some luck the revisions can be mapped to the pci subsystem id (there is some evidence indicating that this might be the case). Provided there is a strict mapping, _if_ WOL ever makes it into via-rhine.c, we had better match subsystem ids and throw an error message or something if a user tries to enable WOL with a board that doesn't support it. Otherwise it's easy to predict a new FAQ.

Roger