Added warning on software deveui override by HW one

src/loraconf.sample.h

@@ -12,6 +12,8 @@
 // Set your DEVEUI here, if you have one. You can leave this untouched, 
 // then the DEVEUI will be generated during runtime from device's MAC adress
 // Note: Use same format as in TTN console (cut & paste, for your convenience)
+// *** Take care : If Using a board with Microchip 24AA02E64 Uinique ID for deveui, **
+// *** this DEVEUI will be overwriten by the one contained in the Microchip module ***
 static const u1_t DEVEUI[8]={ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
 
 // Note: Use msb format for APPEUI as in TTN console (cut & paste, for your convenience)