ASoC: txx9: Replace tasklet with work

The tasklet is an old API that should be deprecated, usually can be
converted to another decent API.  In ASoC TXx9 ACLC driver, a tasklet
is still used for offloading the hardware reset function.  It can be
achieved gracefully with a work queued, too.

This patch replaces the tasklet usage in TXx9 ACLC driver with a
simple work.  The conversion is fairly straightforward.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20200903104749.21435-4-tiwai@suse.de
Signed-off-by: Mark Brown <broonie@kernel.org>