[gtksourceview] build: fix gtk minor version check for ABI

[Christian Hergert <chergert src gnome org>]

commit ccaa358ccda2f9635deea61fab58ed7244412799
Author: Christian Hergert <chergert redhat com>
Date:   Thu Jan 6 19:41:12 2022 -0800

    build: fix gtk minor version check for ABI

 meson.build | 4 ++++
 1 file changed, 4 insertions(+)
---
diff --git a/meson.build b/meson.build
index 236898eb..904e1827 100644
--- a/meson.build
+++ b/meson.build
@@ -118,6 +118,10 @@ gtk_version_arr = gtk_req_version.split('.')
 gtk_major_version = gtk_version_arr[0]
 gtk_minor_version = gtk_version_arr[1]
 
+if gtk_minor_version.to_int() % 2 == 1
+  gtk_minor_version = '@0@'.format(gtk_minor_version.to_int()+1)
+endif
+
 deprecated_c_args = [
   '-DG_DISABLE_DEPRECATED',
   '-DGDK_DISABLE_DEPRECATED',