ASoC: rt5645: set RT5645_PRIV_INDEX as volatile

RT5645_PRIV_INDEX(0x6a) indicate the address of PR- registers. So,
it should be volatile.

Signed-off-by: Bard Liao <bardliao@realtek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
1 file changed