Userguide Wifi workshop: better wifi firmware docs

[nephele]

The section about wifi firmwares should mention which broadcom devices are supported currently.

One user had problems in irc because their BCM4313 device was unsupported, but the userguide sais "Broadcom 43XX" firmware.

​https://www.haiku-os.org/docs/userguide/en/workshop-wlan.html

Relevant: https://dev.haiku-os.org/ticket/6480

[humdinger]

If there is a list of supported models of our driver, we can add it or link to it.

Otherwise I imagine these historic chipsets are so rare that it's quite improbably for someone to make a list of the supported models. In that case we could weasle in a "some Broadcom 43xx chipsets". Not much use, but it doesn't get the hopes up too much for the poor antiquarian user... :)

[waddlesplash]

I think the supported ones are: BCM4301, BCM4306, BCM4307, BCM4309, BCM4311, BCM4312, BCM4318.

But Broadcom's device numbering is so confusing that there may be some which sound like these but aren't supported...