ALSA: timer: Constify snd_timer_hardware definitions

Most of snd_timer_hardware definitions do simply copying to another
struct as-is.  Mark them as const for further optimization.

There should be no functional changes by this patch.

Link: https://lore.kernel.org/r/20200103081714.9560-21-tiwai@suse.deSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/core/pcm_timer.c

@@ -75,7 +75,7 @@ static int snd_pcm_timer_stop(struct snd_timer * timer)
 	return 0;
 }
 
-static struct snd_timer_hardware snd_pcm_timer =
+static const struct snd_timer_hardware snd_pcm_timer =
 {
 	.flags =	SNDRV_TIMER_HW_AUTO | SNDRV_TIMER_HW_SLAVE,
 	.resolution =	0,

sound/core/timer.c

@@ -1199,7 +1199,7 @@ static int snd_timer_s_close(struct snd_timer *timer)
 	return 0;
 }
 
-static struct snd_timer_hardware snd_timer_system =
+static const struct snd_timer_hardware snd_timer_system =
 {
 	.flags =	SNDRV_TIMER_HW_FIRST | SNDRV_TIMER_HW_TASKLET,
 	.resolution =	1000000000L / HZ,