ASoc: tas2781: Add name_prefix as the prefix name of firmwares and kcontrol to support corresponding TAS2563/TAS2781s

Add name_prefix as the prefix name of firmwares and
kcontrol to support corresponding TAS2563/TAS2781s.
name_prefix is not mandatory.
Signed-off-by: Shenghao Ding <shenghao-ding@ti.com>
Link: https://patch.msgid.link/20240621132309.564-1-shenghao-ding@ti.comSigned-off-by: Mark Brown <broonie@kernel.org>