docs: Fix duplicate label error for network.WLAN.

docs/library/network.rst

@@ -178,13 +178,13 @@ For example::
     
        Dump the WIZnet5x00 registers.  Useful for debugging.
 
+class WLAN
+==========
+
+.. _network.WLAN:
+
 .. only:: port_esp8266
 
-    class WLAN
-    ==========
-
-    .. _network.WLAN:
-
     This class provides a driver for WiFi network processor in the ESP8266.  Example usage::
 
         import network
@@ -238,11 +238,6 @@ For example::
 
 .. only:: port_wipy
 
-    class WLAN
-    ==========
-
-    .. _network.WLAN:
-
     This class provides a driver for WiFi network processor in the WiPy.  Example usage::
     
         import network