ASoC: SOF: compress: Remove dai_posn variable

dai_posn is set but never used. Initial intention was
to use dai_posn to shorthen one code line but it looks fine
without it too.

Fixes: c1a731c7 ("ASoC: SOF: compress: Add support for computing timestamps")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
Link: https://lore.kernel.org/r/20220822174937.254873-1-daniel.baluta@oss.nxp.com


Signed-off-by: Mark Brown <broonie@kernel.org>