[gtk/ebassi/for-master: 5/7] build: Remove duplicate definition

[Emmanuele Bassi <ebassi src gnome org>]

commit e75e44bdcca3d687ee2b260910180caba6386095
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Tue Dec 15 11:47:32 2020 +0000

    build: Remove duplicate definition
    
    The `GTK_COMPILATION` symbol is defined in gir_args.

 gtk/meson.build | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)
---
diff --git a/gtk/meson.build b/gtk/meson.build
index ffadb28267..7d2d1e1c83 100644
--- a/gtk/meson.build
+++ b/gtk/meson.build
@@ -1231,9 +1231,7 @@ if build_gir
                                header: 'gtk/gtk.h',
                                install: true,
                                dependencies: gsk_gir_dep,
-                               extra_args: gir_args + [
-                                 '-DGTK_COMPILATION',
-                               ])
+                               extra_args: gir_args)
   gtk_dep_sources += gtk_gir
 endif