backends/x11: Stop translating a property ID

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Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1593>

src/backends/x11/meta-input-device-x11.c

@@ -288,8 +288,8 @@ meta_input_device_x11_class_init (MetaInputDeviceX11Class *klass)
 
   props[PROP_ID] =
     g_param_spec_int ("id",
-                      P_("Id"),
+                      "Id",
-                      P_("Unique identifier of the device"),
+                      "Unique identifier of the device",
                       -1, G_MAXINT,
                       0,
                       CLUTTER_PARAM_READWRITE |