ASoC: amd: Modified DMA transfer Mechanism for Playback

Before rendering starts, DMA driver copies full buffer valid data
to ACP SRAM for the first time, after that ACP SRAM to I2S
FIFO DMA will be initiated. After rendering first half of ACP SRAM,
IOC will be raised then Audio data will be copied from first half of
System Memory to first half of ACP SRAM. Similarly after rendering
second half of ACP SRAM, IOC will be raised then Audio Data will be
copied from second half of the System Memory to second half of the
ACP SRAM in ping-pong way till rendering stops.

Old design introducing latency issues resulting stutter sound observed
during playback.

Signed-off-by: Vijendar Mukunda <Vijendar.Mukunda@amd.com>
Signed-off-by: Akshu Agrawal <Akshu.Agrawal@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Mark Brown <broonie@kernel.org>