PMSA0031 sensors require ~3secs before coming up on I2C (#4743)

* PMSA0031 sensors require ~3secs before coming up on I2C

As reported by @MALAONE1 and debugged by @shodan8192 , PMSA0031s
on a RAK4631 take 3 seconds before they can become detectable on I2c.

Add a delay(4000) before I2C scan if the air quality sensor pin
is defined.

Fixes https://github.com/meshtastic/firmware/issues/3690

* Remove 4 second wait and rescan during air quality init for the sensor

* works without but this triggers my OCD

---------

Co-authored-by: Thomas Göttgens <tgoettgens@gmail.com>
Co-authored-by: Ben Meadors <benmmeadors@gmail.com>

src/main.cpp

@@ -390,7 +390,7 @@ void setup()
 #endif
 
 #ifdef AQ_SET_PIN
-    // RAK-12039 set pin for Air quality sensor
+    // RAK-12039 set pin for Air quality sensor. Detectable on I2C after ~3 seconds, so we need to rescan later
     pinMode(AQ_SET_PIN, OUTPUT);
     digitalWrite(AQ_SET_PIN, HIGH);
 #endif
@@ -1142,4 +1142,4 @@ void loop()
     }
     // if (didWake) LOG_DEBUG("wake!\n");
 }
-#endif
+#endif