fix is_available method of btchip plugin

plugins/btchipwallet.py

@@ -54,12 +54,11 @@ class Plugin(BasePlugin):
         return BTCHIP
 
     def is_available(self):
-        #if self.wallet is None:
-        #    return self._is_available
-        #if self.wallet.storage.get('wallet_type') == 'btchip':
-        #    return True
-        #return False
-        return self._is_available
+        if self.wallet is None:
+            return self._is_available
+        if self.wallet.storage.get('wallet_type') == 'btchip':
+            return True
+        return False
 
     def set_enabled(self, enabled):
         self.wallet.storage.put('use_' + self.name, enabled)