ice.4: Update man page with feature documentation

[ricera]

This is eventually supposed to document the functionality from @kgalazka's #1573, but for now it contains information ported from the out-of-tree driver's man pages in order to bring the current man page up to date with features that are already in the upstream driver.

[concussious]

Not all heroes wear capes.

[ricera]

I have some additional concerns and questions that I hope someone can answer:

• Should "information on enabling VLANs, see the README" be removed or add another link to ifconfig(8)? Or the VLAN man page? The README isn't shipped upstream, so I don't think it's sensible to direct users to the README. Plus, basic vlan features aren't very complicated.

• I don't know if ".Em" is the correct way to highlight the names of the utilities like below: .Em Ethernet Port Configuration Tool - FreeBSD

• Not sure how to format "NOTE:" lines; for now I just left their formatting as standard text.

• I don't think ice_ddp has a man page or maybe should even get one. How do I refer to it without using .Xr?

• @kgalazka Need to add 200G modules to the list in the HARDWARE section, but I don't know any of their SKUs or descriptions

• @kgalazka, for "mirror-src-vsi" iovctl parameter, how do you find the vsi number for the PF VSI? I cannot remember -- is it indexed to the driver (so it would be 0) or is it indexed to a value from the FW/HW?

[concussious]

Should "information on enabling VLANs, see the README" be removed or add another link to ifconfig(8)? Or the VLAN man page? The README isn't shipped upstream, so I don't think it's sensible to direct users to the README. Plus, basic vlan features aren't very complicated.

If we don't have the readme, ifconfig sounds good to me.

I don't know if ".Em" is the correct way to highlight the names of the utilities like below: .Em Ethernet Port Configuration Tool - FreeBSD

"If such a stand-alone command is the topic of the current manual page, use Nm; if it is documented in another manual page, use Xr; otherwise, if it is not documented, for example because it is only available in foreign or historical operating systems, use Sy." ~https://mandoc.bsd.lv/mdoc/style/commands.html

But what is Ethernet port configuration tool FreeBSD? If we can get that in ports, it should be something like:

.Sy portcfgtoolname
.Pq Pa ports/net/intel_ethernet_conftool

Not sure how to format "NOTE:" lines; for now I just left their formatting as standard text.

That's usually what I do, and I usually say "Note that..." to reinforce that I'm intending it as standard text.

I don't think ice_ddp has a man page or maybe should even get one. How do I refer to it without using .Xr?

.Sy

Thanks again. This is a big deal. The doc is what sells the users on it, I think.

[kgalazka]

[ricera]

Since #1573 was recently merged, I've rebased this. Any other suggestions or fixes that I should make?

[ricera]

@concussious I included your other suggestions, and pushed this into main. You're now free to do your refactor on it!