add 1 more IPAddress constructor for IPv6 (#5551)

Author: d-a-v

Diff for: cores/esp8266/IPAddress.cpp

@@ -187,6 +187,11 @@ const IPAddress INADDR_NONE(255,255,255,255);
 
 #if LWIP_IPV6
 
+IPAddress::IPAddress(const ip_addr_t* from)
+{
+    ip_addr_copy(_ip, *from);
+}
+
 bool IPAddress::fromString6(const char *address) {
     // TODO: test test test
 

Diff for: cores/esp8266/IPAddress.h

@@ -163,6 +163,8 @@ class IPAddress: public Printable {
 
 #if LWIP_IPV6
 
+        IPAddress(const ip_addr_t* from);
+
         uint16_t* raw6()
         {
             setV6();

Diff for: libraries/ESP8266WiFi/examples/IPv6/IPv6.ino

@@ -98,7 +98,11 @@ void setup() {
   Serial.println();
   Serial.println(ESP.getFullVersion());
 
-  Serial.printf("IPV6 is%s enabled\n", LWIP_IPV6 ? emptyString.c_str() : " NOT");
+#if LWIP_IPV6
+  Serial.printf("IPV6 is enabled\n");
+#else
+  Serial.printf("IPV6 is not enabled\n");
+#endif
 
   WiFi.mode(WIFI_STA);
   WiFi.begin(STASSID, STAPSK);