ALSA: hda: Constify snd_device_ops definitions

Now we may declare const for snd_device_ops definitions, so let's do
it for optimization.

There should be no functional changes by this patch.

Link: https://lore.kernel.org/r/20200103081714.9560-9-tiwai@suse.deSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/hda/hda_beep.c

@@ -192,7 +192,7 @@ static int beep_dev_free(struct snd_device *device)
  */
 int snd_hda_attach_beep_device(struct hda_codec *codec, int nid)
 {
-	static struct snd_device_ops ops = {
+	static const struct snd_device_ops ops = {
 		.dev_register = beep_dev_register,
 		.dev_disconnect = beep_dev_disconnect,
 		.dev_free = beep_dev_free,

sound/pci/hda/hda_codec.c

@@ -915,7 +915,7 @@ int snd_hda_codec_device_new(struct hda_bus *bus, struct snd_card *card,
 	char component[31];
 	hda_nid_t fg;
 	int err;
-	static struct snd_device_ops dev_ops = {
+	static const struct snd_device_ops dev_ops = {
 		.dev_register = snd_hda_codec_dev_register,
 		.dev_free = snd_hda_codec_dev_free,
 	};

sound/pci/hda/hda_intel.c

@@ -1743,7 +1743,7 @@ static int azx_create(struct snd_card *card, struct pci_dev *pci,
 		      int dev, unsigned int driver_caps,
 		      struct azx **rchip)
 {
-	static struct snd_device_ops ops = {
+	static const struct snd_device_ops ops = {
 		.dev_disconnect = azx_dev_disconnect,
 		.dev_free = azx_dev_free,
 	};

sound/pci/hda/hda_tegra.c

@@ -366,7 +366,7 @@ static int hda_tegra_create(struct snd_card *card,
 			    unsigned int driver_caps,
 			    struct hda_tegra *hda)
 {
-	static struct snd_device_ops ops = {
+	static const struct snd_device_ops ops = {
 		.dev_disconnect = hda_tegra_dev_disconnect,
 		.dev_free = hda_tegra_dev_free,
 	};