[#4616] Fix addressbook warnings

sflphone-client-gnome/src/contacts/addressbook.c

@@ -96,7 +96,6 @@ addressbook_is_active()
 static void
 addressbook_config_books()
 {
-
     gchar **config_book_uid;
     book_data_t *book_data;
     gchar **list;
@@ -104,7 +103,8 @@ addressbook_config_books()
     // Retrieve list of books
     list = (gchar **) dbus_get_addressbook_list();
 
-    if (list) {
+    if (list == NULL)
+        return;
 
     for (config_book_uid = list; *config_book_uid; config_book_uid++) {
 
@@ -112,8 +112,9 @@ addressbook_config_books()
         book_data = books_get_book_data_by_uid (*config_book_uid);
 
         // If book_data exists
-            if (!book_data) {
+        if (book_data == NULL) {
             ERROR ("Addressbook: Error: Could not open book (%s:%d)", __FILE__, __LINE__);
+        } else {
             book_data->active = TRUE;
         }
     }
@@ -121,8 +122,6 @@ addressbook_config_books()
     g_strfreev (list);
 }
 
-}
-
 /**
  * Good method to get books_data
  */