Rename additional_animation to animation as it makes more sense

Label all vehicle animation types based on loading relevant parks

src/openrct2/ride/RideData.cpp

@@ -1598,7 +1598,7 @@ const rct_ride_entry_vehicle CableLiftVehicle = {
     /* .sprite_width = */ 0,
     /* .sprite_height_negative = */ 0,
     /* .sprite_height_positive = */ 0,
-    /* .additional_animation = */ 0,
+    /* .animation = */ 0,
     /* .flags = */ 0,
     /* .base_num_frames = */ 1,
     /* .base_image_id = */ 29110,