UI: Unhide the world mist panel if the mist pass is not enabled

This makes no sense to hide it since we can nowadays preview it inside the
viewport even if the render pass is not enabled.

release/scripts/startup/bl_ui/properties_world.py

@@ -46,12 +46,7 @@ class EEVEE_WORLD_PT_mist(WorldButtonsPanel, Panel):
     @classmethod
     def poll(cls, context):
         engine = context.engine
-        if context.world and (engine in cls.COMPAT_ENGINES):
-            for view_layer in context.scene.view_layers:
-                if view_layer.use_pass_mist:
-                    return True
-
-        return False
+        return context.world and (engine in cls.COMPAT_ENGINES)
 
     def draw(self, context):
         layout = self.layout