sound: Fix Kconfig indentation

sound: Fix Kconfig indentation

Adjust indentation from spaces to tab (+optional two spaces) as in
coding style with command like:
    $ sed -e 's/^        /\t/' -i */Kconfig

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20191004144931.3851-1-krzk@kernel.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>