idle-notify: make wl_global public

I wish to use a allowlist of globals for my security context
implementation rather than a blocklist, which means I need access to
the ext_idle_notifier_v1 global in order to allowlist it.

I think using a allowlist will make it harder for me to accidentally
expose globals to a security context that were meant to be restricted.

include/wlr/types/wlr_idle_notify_v1.h

@@ -16,7 +16,17 @@ struct wlr_seat;
 /**
  * An idle notifier, implementing the ext-idle-notify-v1 protocol.
  */
-struct wlr_idle_notifier_v1;
+struct wlr_idle_notifier_v1 {
+	struct wl_global *global;
+
+	// private state
+
+	bool inhibited;
+	struct wl_list notifications; // wlr_idle_notification_v1.link
+
+	struct wl_listener display_destroy;
+};
+
 
 /**
  * Create the ext_idle_notifier_v1 global.

types/wlr_idle_notify_v1.c

@@ -6,15 +6,6 @@
 
 #define IDLE_NOTIFIER_VERSION 1
 
-struct wlr_idle_notifier_v1 {
-	struct wl_global *global;
-
-	bool inhibited;
-	struct wl_list notifications; // wlr_idle_notification_v1.link
-
-	struct wl_listener display_destroy;
-};
-
 struct wlr_idle_notification_v1 {
 	struct wl_resource *resource;
 	struct wl_list link; // wlr_idle_notifier_v1.notifications