Enhancement: Dynamic tooltip for wireless modes

[billz]

Is your feature request related to a problem?

The Hotspot > Basic tab allows users to select any available wireless mode, even if the hardware for the selected interface does not support it. This can lead to confusion when hostapd fails to start. See for example Can't change WiFi channel, using RaspAP, on Raspberry Pi 3B.

Describe the solution you'd like

Supported wireless modes should be queried with iw phy for the selected interface. The availability of one or more supported bands could be used in a tooltip to provide context for the user, eg.:

Worth noting that an adapter may support a given mode, while the driver does not. Also iw info outputs a lot of detail. It's possible to resolve bitrates, channel widths, etc. however for this first stab I'd opt for 2.4 versus 5 GHz support (or both).

Additional context

The 802.11ac 5 GHz mode is disabled until a compatible wireless regulatory domain is defined by the user. I think this has prevented confusion for users who want this mode but have not done the prerequisite steps to enable it. A context sensitive tooltip could also be potentially useful in this case.

From a UX perspective, I feel a tooltip is preferable to disabling more dropdown items. Suggestions are welcome.

Related to #872