adds temporary fallbacks for esp32 set country

Find better way to check version feature check, arduino ver is not always available.

WiFiManager.cpp

@@ -3457,8 +3457,14 @@ bool WiFiManager::WiFiSetCountry(){
   // If an invalid country code is passed, ESP_ERR_WIFI_ARG will be returned
   // This also uses 802.11d mode, which matches the STA to the country code of the AP it connects to (meaning
   // that the country code will be overridden if connecting to a "foreign" AP)
-  else err = esp_wifi_set_country_code(_wificountry.c_str(), true);
-
+  else {
+    #ifndef WM_NOCOUNTRY
+    err = esp_wifi_set_country_code(_wificountry.c_str(), true);
+    #else
+    DEBUG_WM(DEBUG_ERROR,"[ERROR] esp wifi set country is not available");
+    err = true;
+    #endif
+  }
   #ifdef WM_DEBUG_LEVEL
     if(err){
       if(err == ESP_ERR_WIFI_NOT_INIT) DEBUG_WM(DEBUG_ERROR,"[ERROR] ESP_ERR_WIFI_NOT_INIT");

WiFiManager.h

@@ -638,10 +638,18 @@ class WiFiManager
             #define WM_ARDUINOEVENTS
         #else
             #define WM_NOSOFTAPSSID
+            #define WM_NOCOUNTRY
         #endif
 
+    #else 
+        #define WM_NOCOUNTRY
     #endif
 
+    #ifdef WM_NOCOUNTRY
+        #warning "ESP32 set country unavailable" 
+    #endif
+
+
     #ifdef WM_ARDUINOEVENTS
         void   WiFiEvent(WiFiEvent_t event, arduino_event_info_t info);
     #else

examples/Super/OnDemandConfigPortal/OnDemandConfigPortal.ino

@@ -219,7 +219,7 @@ void setup() {
   // setting wifi country seems to improve OSX soft ap connectivity, 
   // may help others as well, default is CN which has different channels
 
-  // wm.setCountry("US"); // crashing on esp32 2.0
+  wm.setCountry("US"); // crashing on esp32 2.0
 
   // set Hostname