ALSA: ice1724: Use snd_ctl_enum_info()

... and reduce the open codes.  Also add missing const to text arrays.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/ice1712/ice1724.c b/sound/pci/ice1712/ice1724.c
index 08cb08a..f633e3b 100644
--- a/sound/pci/ice1712/ice1724.c
+++ b/sound/pci/ice1712/ice1724.c
@@ -2049,13 +2049,7 @@
 		"IEC958 In L", "IEC958 In R", /* 3-4 */
 	};
 
-	uinfo->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
-	uinfo->count = 1;
-	uinfo->value.enumerated.items = 5;
-	if (uinfo->value.enumerated.item >= uinfo->value.enumerated.items)
-		uinfo->value.enumerated.item = uinfo->value.enumerated.items - 1;
-	strcpy(uinfo->value.enumerated.name, texts[uinfo->value.enumerated.item]);
-	return 0;
+	return snd_ctl_enum_info(uinfo, 1, 5, texts);
 }
 
 static inline int analog_route_shift(int idx)