ASoC: Enforce the mask in snd_soc_update_bits()

Avoids issues if someone does a read followed by restore and doesn't mask
out only the bits being updated.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@ti.com>

sound/soc/soc-core.c

@@ -2323,7 +2323,7 @@ int snd_soc_update_bits(struct snd_soc_codec *codec, unsigned short reg,
 		return ret;
 
 	old = ret;
-	new = (old & ~mask) | value;
+	new = (old & ~mask) | (value & mask);
 	change = old != new;
 	if (change) {
 		ret = snd_soc_write(codec, reg, new);