ASoC: tas2770: clean up an indentation issue

There is a block that is indented too deeply, remove
the extraneous tabs.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20191112190218.282337-1-colin.king@canonical.comSigned-off-by: Mark Brown <broonie@kernel.org>