ASoC: amd: update ps platform acp header file

Rename Audio buffer and soundwire manager instance registers.
Remove scratch registers as these registers can be accessed
using ACP_SCRATCH_REG_0 register relative offset.
Signed-off-by: Vijendar Mukunda <Vijendar.Mukunda@amd.com>
Link: https://lore.kernel.org/r/20230201165626.3169041-1-Vijendar.Mukunda@amd.comSigned-off-by: Mark Brown <broonie@kernel.org>