Update the phy context routines to match what the openbsd snapshot
is doing. This involves some HT channel width stuff which although
I am not doing HT right now, it was juts easier to sync these
entirely versus just a partial sync.

• Update the phy context routines to match what openbsd is doing
• Although the openbsd driver has an iwm_phy_ctxt_update() routine instead of add and modify, I'm leaving it as-is for now. A bunch of refactoring is going to need to be done to properly use an iwm_phy_ctxt_update() call and I didn't want to tackle that in here.
• Add a UHB firmware capability phy context call; I can't test it but it's mostly copy/paste.
• Add in a util to turn ieee80211_channel into the 'sco' variable (the HT low/hi parameter) since it's done in openbsd in a slightly different way.

Locally tested:

• 7260, STA mode
• 9260, STA mode

Obtained from: OpenBSD a6e25c727a2214219715b51ba6af2221d7e0d674