Move update_if_necessary to util.c, will be necessary later

include/util.h

@@ -41,6 +41,13 @@ extern struct keyvalue_table_head by_child;
 int min(int a, int b);
 int max(int a, int b);
 
+/**
+ * Updates *destination with new_value and returns true if it was changed or false
+ * if it was the same
+ *
+ */
+bool update_if_necessary(uint32_t *destination, const uint32_t new_value);
+
 /**
  * Safe-wrapper around malloc which exits if malloc returns NULL (meaning that
  * there is no more memory available)