[gnome-nettool/wip/jtojnar/meson-cleanups: 3/6] meson: avoid deprecated meson.source_root() function

[Jan Tojnar <jtojnar src gnome org>]

commit 964f5fc3cab9efc4959f930ac380c0dc4c3b0490
Author: Jan Tojnar <jtojnar gmail com>
Date:   Tue Sep 27 04:47:11 2022 +0200

    meson: avoid deprecated meson.source_root() function
    
    To avoid the followin warning:
    
        WARNING: Deprecated features used:
         * 0.56.0: {'meson.source_root'}

 meson.build | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/meson.build b/meson.build
index 0a11b30..6bb2683 100644
--- a/meson.build
+++ b/meson.build
@@ -6,7 +6,7 @@ project(
     'buildtype=debugoptimized',
     'warning_level=1',
   ],
-  meson_version: '>= 0.40.1',
+  meson_version: '>= 0.56.0',
   license: 'GPL-2.0-or-later',
 )
 
@@ -54,7 +54,7 @@ nettool_deps = [
   gtop_dep,
 ]
 
-po_dir = join_paths(meson.source_root(), 'po')
+po_dir = join_paths(meson.project_source_root(), 'po')
 
 subdir('src')
 subdir('po')