[gobject-introspection] girepository: Add 1.66 version macro

[Emmanuele Bassi <ebassi src gnome org>]

commit bcf8fa77d7946ce6285866b36b9c0d8134861109
Author: Philip Chimento <philip chimento gmail com>
Date:   Sat Apr 11 14:19:06 2020 -0700

    girepository: Add 1.66 version macro
    
    Required for adding new API to the 1.66 series.

 girepository/giversionmacros.h | 6 ++++++
 1 file changed, 6 insertions(+)
---
diff --git a/girepository/giversionmacros.h b/girepository/giversionmacros.h
index c32e5bb8..a941ee2d 100644
--- a/girepository/giversionmacros.h
+++ b/girepository/giversionmacros.h
@@ -159,4 +159,10 @@
 # define GI_AVAILABLE_IN_1_60                 _GI_EXTERN
 #endif
 
+#if defined(GLIB_VERSION_2_66) && GLIB_VERSION_MAX_ALLOWED < GLIB_VERSION_2_66
+# define GI_AVAILABLE_IN_1_66                 GLIB_UNAVAILABLE(2, 66)
+#else
+# define GI_AVAILABLE_IN_1_66                 _GI_EXTERN
+#endif
+
 #endif /* __GIVERSIONMACROS_H__ */