ASoC: Intel: sst: Fix the return value of 'sst_send_byte_stream_mrfld()'

[ Upstream commit eaadb1caa966a91128297b754e90b7c92b350a00 ]

In some error handling paths, an error code is assiegned to 'ret'.
However, the function always return 0.

Fix it and return the error code if such an error paths is taken.

Fixes: 3d9ff346 ("ASoC: Intel: sst: add stream operations")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>