ASoC: SOF: Intel: set the DMA TLV device as dai_index

ASoC: SOF: Intel: set the DMA TLV device as dai_index

We've already defined the value for dai_index, let's use it instead of
open-coding the same thing. No functionality change.

Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://msgid.link/r/20240402151828.175002-9-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>