tnl: Silence unused parameter warnings in dump_draw_info

tnl: Silence unused parameter warnings in dump_draw_info

src/mesa/tnl/t_split_copy.c: In function ‘dump_draw_info’:
src/mesa/tnl/t_split_copy.c:149:35: warning: unused parameter ‘ctx’ [-Wunused-parameter]
  149 | dump_draw_info(struct gl_context *ctx,
      |                ~~~~~~~~~~~~~~~~~~~^~~
src/mesa/tnl/t_split_copy.c:154:23: warning: unused parameter ‘min_index’ [-Wunused-parameter]
  154 |                GLuint min_index,
      |                ~~~~~~~^~~~~~~~~
src/mesa/tnl/t_split_copy.c:155:23: warning: unused parameter ‘max_index’ [-Wunused-parameter]
  155 |                GLuint max_index)
      |                ~~~~~~~^~~~~~~~~

Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4512>