Cleanup: remove redundant preferences.inputs.use_ndof

This is available via: bpy.app.build_options.input_ndof

scripts/startup/bl_ui/space_userpref.py

@@ -1812,9 +1812,7 @@ class USERPREF_PT_input_ndof(InputPanel, CenterAlignMixIn, Panel):
 
     @classmethod
     def poll(cls, context):
-        prefs = context.preferences
-        inputs = prefs.inputs
-        return inputs.use_ndof
+        return bpy.app.build_options.input_ndof
 
     def draw_centered(self, context, layout):
         prefs = context.preferences

source/blender/makesrna/intern/rna_userdef.cc

@@ -6501,14 +6501,7 @@ static void rna_def_userdef_input(BlenderRNA *brna)
       prop,
       "Lock Camera Pan/Zoom",
       "Pan/zoom the camera view instead of leaving the camera view when orbiting");
-
-  /* let Python know whether NDOF is enabled */
-  prop = RNA_def_boolean(srna, "use_ndof", true, "", "");
-#  else
-  prop = RNA_def_boolean(srna, "use_ndof", false, "", "");
 #  endif /* WITH_INPUT_NDOF */
-  RNA_def_property_flag(prop, PROP_IDPROPERTY);
-  RNA_def_property_clear_flag(prop, PROP_EDITABLE);
 
   prop = RNA_def_property(srna, "mouse_double_click_time", PROP_INT, PROP_NONE);
   RNA_def_property_int_sdna(prop, nullptr, "dbl_click_time");