ASoC: rsnd: ssi: fix race condition in rsnd_ssi_pointer_update

ASoC: rsnd: ssi: fix race condition in rsnd_ssi_pointer_update

Currently there is race condition between set of byte_pos and wrap
it around when new buffer starts. If .pointer is called in-between
it will result in inconsistent pointer position be returned
from .pointer callback.

This patch increments buffer pointer atomically to avoid this issue.

Signed-off-by: Jiada Wang <[email protected]>
Reviewed-by: Takashi Sakamoto <[email protected]>
Acked-by: Kuninori Morimoto <[email protected]>
Signed-off-by: Mark Brown <[email protected]>