* MESHTASTIC_EXCLUDE_WIFI and HAS_WIFI cleanup...
Our code was checking HAS_WIFI and the new MESHTASTIC_EXCLUDE_WIFI
flags in various places (even though EXCLUDE_WIFI forces HAS_WIFI
to 0). Instead just check HAS_WIFI, only use EXCLUDE_WIFI inside
configuration.h
* cleanup: use HAS_NETWORKING instead of HAS_WIFI || HAS_ETHERNET
We already had HAS_NETWORKING as flag in MQTT to mean 'we have
tcpip'. Generallize that and move it into configuration.h so that
we can use it elsewhere.
* Use #pragma once, because supported by gcc and all modern compilers
instead of #ifdef DOTHFILE_H etc...
---------
Co-authored-by: Jonathan Bennett <jbennett@incomsystems.biz>
* Pico W: Initial WiFi support: connects, but freezes after a while
* Update arduino-pico core to fix hang with Wi-Fi
* Add `picow` to workflow since it's different from `pico` now
