ASoC : cs4265 : readable register too low

The cs4265_readable_register function stopped short of the maximum
register.

An example bug is taken from :
https://github.com/Audio-Injector/Ultra/issues/25

Where alsactl store fails with :
Cannot read control '2,0,0,C Data Buffer,0': Input/output error

This patch fixes the bug by setting the cs4265 to have readable
registers up to the maximum hardware register CS4265_MAX_REGISTER.
Signed-off-by: NMatt Flax <flatmax@flatmax.org>
Reviewed-by: NCharles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

sound/soc/codecs/cs4265.c

@@ -60,7 +60,7 @@ static const struct reg_default cs4265_reg_defaults[] = {
 static bool cs4265_readable_register(struct device *dev, unsigned int reg)
 {
 	switch (reg) {
-	case CS4265_CHIP_ID ... CS4265_SPDIF_CTL2:
+	case CS4265_CHIP_ID ... CS4265_MAX_REGISTER:
 		return true;
 	default:
 		return false;