of/reconfig: Add empty stubs for the of_reconfig methods

To simplify subsystem setup code, make empty stubs for the
of_reconfig_*() methods. This is particularly useful for registering and
unregistering the notifiers so that it doesn't impact the flow of the
subsystem setup code.

Signed-off-by: Grant Likely <grant.likely@linaro.org>

include/linux/of.h

@@ -324,11 +324,6 @@ struct of_prop_reconfig {
 	struct property		*old_prop;
 };
 
-extern int of_reconfig_notifier_register(struct notifier_block *);
-extern int of_reconfig_notifier_unregister(struct notifier_block *);
-extern int of_reconfig_notify(unsigned long, void *);
-extern int of_reconfig_get_state_change(unsigned long action, void *arg);
-
 extern int of_attach_node(struct device_node *);
 extern int of_detach_node(struct device_node *);
 
@@ -895,6 +890,11 @@ enum of_reconfig_change {
 };
 
 #ifdef CONFIG_OF_DYNAMIC
+extern int of_reconfig_notifier_register(struct notifier_block *);
+extern int of_reconfig_notifier_unregister(struct notifier_block *);
+extern int of_reconfig_notify(unsigned long, void *);
+extern int of_reconfig_get_state_change(unsigned long action, void *arg);
+
 extern void of_changeset_init(struct of_changeset *ocs);
 extern void of_changeset_destroy(struct of_changeset *ocs);
 extern int of_changeset_apply(struct of_changeset *ocs);
@@ -932,7 +932,24 @@ static inline int of_changeset_update_property(struct of_changeset *ocs,
 {
 	return of_changeset_action(ocs, OF_RECONFIG_UPDATE_PROPERTY, np, prop);
 }
-#endif
+#else /* CONFIG_OF_DYNAMIC */
+static inline int of_reconfig_notifier_register(struct notifier_block *nb)
+{
+	return -EINVAL;
+}
+static inline int of_reconfig_notifier_unregister(struct notifier_block *nb)
+{
+	return -EINVAL;
+}
+static inline int of_reconfig_notify(unsigned long action, void *arg)
+{
+	return -EINVAL;
+}
+static inline int of_reconfig_get_state_change(unsigned long action, void *arg)
+{
+	return -EINVAL;
+}
+#endif /* CONFIG_OF_DYNAMIC */
 
 /* CONFIG_OF_RESOLVE api */
 extern int of_resolve_phandles(struct device_node *tree);