soundwire: qcom: check for outanding writes before doing a read

[ Upstream commit 49a46731 ]

Reading will increase the fifo count, so check for outstanding cmd wrt.
write fifo depth to avoid overflow as read will also increase
write fifo cnt.

Fixes: a661308c

 ("soundwire: qcom: wait for fifo space to be available before read/write")
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20221026110210.6575-3-srinivas.kandagatla@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>