ASoC: qdsp6: audioreach: Constify struct snd_soc_tplg_ops

Constifying "struct snd_soc_tplg_ops" moves some data to a read-only
section, so increase overall security.

On a x86_64, with allmodconfig:
Before:
   text	   data	    bss	    dec	    hex	filename
  19942	    832	      0	  20774	   5126	sound/soc/qcom/qdsp6/topology.o

After:
   text	   data	    bss	    dec	    hex	filename
  20102	    652	      0	  20754	   5112	sound/soc/qcom/qdsp6/topology.o
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://msgid.link/r/a5ae843dd8aaacbc1148aea7a3b1d03f11495872.1715526069.git.christophe.jaillet@wanadoo.frSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/qcom/qdsp6/topology.c

@@ -1240,7 +1240,7 @@ static const struct snd_soc_tplg_kcontrol_ops audioreach_io_ops[] = {
 		audioreach_put_vol_ctrl_audio_mixer, snd_soc_info_volsw},
 };
 
-static struct snd_soc_tplg_ops audioreach_tplg_ops  = {
+static const struct snd_soc_tplg_ops audioreach_tplg_ops = {
 	.io_ops = audioreach_io_ops,
 	.io_ops_count = ARRAY_SIZE(audioreach_io_ops),