ASoC: compress: Fix leak of a widget list in soc_compr_open_fe

After we have called dpcm_path_get we should make sure to call
dpcm_path_put on all error paths. This was not happening causing the
allocated widget list to be leaked, this patch corrects this by adding a
dpcm_path_put to the error path.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>