ASoC: twl6040: Use correct offset for LineInAmp Right

Gain for LineInAmp Right uses LINEGAIN[5:3], which means that
offset for right channel should be 4.
Signed-off-by: Misael Lopez Cruz <misael.lopez@ti.com>
Signed-off-by: Margarita Olaya Cabrera <magi.olaya@ti.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>

sound/soc/codecs/twl6040.c

@@ -566,7 +566,7 @@ static const struct snd_kcontrol_new twl6040_snd_controls[] = {
 
 	/* AFM gains */
 	SOC_DOUBLE_TLV("Aux FM Volume",
-		TWL6040_REG_LINEGAIN, 0, 5, 0xF, 0, afm_amp_tlv),
+		TWL6040_REG_LINEGAIN, 0, 4, 0xF, 0, afm_amp_tlv),
 
 	/* Playback gains */
 	SOC_DOUBLE_TLV("Headset Playback Volume",