Allow speed/duplex setting on E810

Hey,

I'm trying to use an Intel E810-C as the receiver for passive optical network taps. I've configured it to provide 8x 10GbE interfaces but Linux is showing no-carrier and I'm not getting any packets.

I've tried using ethtool to set the speed and duplex but both are rejected, and checking the README for this driver it states this isn't supported, which explains why I can't set them.

This appears to be a reasonably regular request from people both for the E810 and in the past for other Intel cards, for example:

* https://sourceforge.net/p/e1000/mailman/e1000-devel/thread/CAA%3DoK3NhKjtXF0VZS0PUb4dLytHaB_%2BsXVZ3Zcu2a4BjuJZ%3DCA%40mail.gmail.com/#msg38634772
* https://sourceforge.net/p/e1000/mailman/e1000-devel/thread/loom.20130505T213619-640%40post.gmane.org/#msg30808659
* https://community.intel.com/t5/Embedded-Intel-Core-Processors/Problem-about-Intel-82599-10-GbE-Controller-help/m-p/188421

I'm using Ubuntu Jammy 20.04 with their 6.8.0 hardware enablement kernel. Tried both the in-kernel ICE driver and the v1.16.3 of the out of tree driver.

Is this something you'd consider supporting?