bcm2835-ctl: limit maximal volume to 4db.

it makes no sense to set 23.04db as maximum volume since around 3db it start to cliping. So with 4db the alsamixer is much better to control. (86% is 0db)

Author: Arne-F

sound/arm/bcm2835-ctl.c

@@ -53,7 +53,7 @@ static int snd_bcm2835_ctl_info(struct snd_kcontrol *kcontrol,
 		uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
 		uinfo->count = 1;
 		uinfo->value.integer.min = -10240;
-		uinfo->value.integer.max = 2303;
+		uinfo->value.integer.max = 400;      /* 2303 */
 	} else if (kcontrol->private_value == PCM_PLAYBACK_MUTE) {
 		uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
 		uinfo->count = 1;