[gtk/gtk-4-4] inspector: Export gtk_inspector_init

[Matthias Clasen <matthiasc src gnome org>]

commit 4c9c180e276c9aca8f0063eb617ad4e7da0f75a9
Author: Matthias Clasen <mclasen redhat com>
Date:   Tue Oct 5 20:09:20 2021 -0400

    inspector: Export gtk_inspector_init
    
    Quietly export this function mainly for the benefit
    of libadwaita, which can can use this to install its
    implementation of the gtk-inspector-page extension
    point.

 gtk/inspector/init.h | 3 +++
 1 file changed, 3 insertions(+)
---
diff --git a/gtk/inspector/init.h b/gtk/inspector/init.h
index 7fe6745fd8..0c7a75e488 100644
--- a/gtk/inspector/init.h
+++ b/gtk/inspector/init.h
@@ -18,8 +18,11 @@
 #ifndef _GTK_INSPECTOR_INIT_H_
 #define _GTK_INSPECTOR_INIT_H_
 
+#include <gdk/gdkversionmacros.h>
+
 G_BEGIN_DECLS
 
+GDK_AVAILABLE_IN_ALL
 void gtk_inspector_init (void);
 
 G_END_DECLS