dbus-utils: Move from the backends/native/ to backends/

We will move the launcher to backends/ which has a dependency on
dbus-utils so let's also just move dbus-utils there.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/4130>

src/backends/meta-dbus-utils.c

@@ -22,7 +22,7 @@
 
 #include "config.h"
 
-#include "backends/native/dbus-utils.h"
+#include "backends/meta-dbus-utils.h"
 
 #include <glib.h>
 

src/backends/native/meta-launcher.c

@@ -32,7 +32,7 @@
 #include <systemd/sd-login.h>
 
 #include "backends/meta-backend-private.h"
-#include "backends/native/dbus-utils.h"
+#include "backends/meta-dbus-utils.h"
 #include "backends/native/meta-backend-native.h"
 #include "backends/native/meta-clutter-backend-native.h"
 #include "backends/native/meta-cursor-renderer-native.h"

src/meson.build

@@ -217,6 +217,8 @@ mutter_sources = [
   'backends/meta-dbus-session-manager.h',
   'backends/meta-dbus-session-watcher.c',
   'backends/meta-dbus-session-watcher.h',
+  'backends/meta-dbus-utils.c',
+  'backends/meta-dbus-utils.h',
   'backends/meta-display-config-shared.h',
   'backends/meta-dnd-private.h',
   'backends/meta-fd-source.c',
@@ -754,8 +756,6 @@ endif
 
 if have_native_backend
   mutter_sources += [
-    'backends/native/dbus-utils.c',
-    'backends/native/dbus-utils.h',
     'backends/native/meta-backend-native.c',
     'backends/native/meta-backend-native.h',
     'backends/native/meta-backend-native-private.h',