wifi_sta_connect_status_() is a non-inlined function call that reads
3 static globals through literal pool indirections on every loop
iteration. Since those globals are only modified during event
processing, skip the call entirely when wifi_loop_() found no
events and we're already in STA_CONNECTED state.
wifi_loop_() now returns bool (true if events were processed) on
all platforms. ESP8266 and Pico W always return true since they
poll state directly rather than using an event queue.
J. Nick Koston
f7222e39bb