ALSA: emu10k1: constify snd_emux_operators structure

Declare snd_emux_operators structure as const as it is only copied into
another structure. So, snd_emux_operators structures having this property
can be made const.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/emu10k1/emu10k1_callback.c

@@ -61,7 +61,7 @@ static void set_filterQ(struct snd_emu10k1 *hw, struct snd_emux_voice *vp);
 /*
  * set up operators
  */
-static struct snd_emux_operators emu10k1_ops = {
+static const struct snd_emux_operators emu10k1_ops = {
 	.owner =	THIS_MODULE,
 	.get_voice =	get_voice,
 	.prepare =	start_voice,