Fix defines

Author: TMRh20

RF24Network.cpp

@@ -1265,15 +1265,15 @@ void ESBNetwork<radio_t>::pipe_address(uint16_t node, uint8_t pipe, uint8_t* add
 }
 
 /******************************************************************/
-
+#if defined ARDUINO_ARCH_ESP8266 || defined ARDUINO_ARCH_ESP32
 template<class radio_t>
 void ESBNetwork<radio_t>::RF24NetworkDelay(uint32_t delay)
 {
     uint32_t timer = millis();
     while (millis() - timer < delay) {
     }
 }
-
+#endif
 /************************ Sleep Mode ******************************************/
 
 #if defined ENABLE_SLEEP_MODE

RF24Network.h

@@ -845,11 +845,13 @@ class ESBNetwork
      */
     uint8_t networkFlags;
 
+#if defined ARDUINO_ARCH_ESP8266 || defined ARDUINO_ARCH_ESP32
     /**
      * Use a regular delay for most devices, but on ESP32 and ESP8266, use a millis() based timeout.
      * See RF24NETWORK_DELAY in RF24Network_config.h
      */
     void RF24NetworkDelay(uint32_t delay);
+#endif
 
 protected:
 #if defined(RF24NetworkMulticast)