ASoC: soc-pcm: fix the invalid access of the memory

dpcm_path_get returns negative if the memory allocatoion has failed.
We should not free the list in this case.
Remove the call dpcm_path_put which releases an invalid memory area.

Change-Id: Ie0122db5117aa65fc6623fbede32f289a0d25326
Signed-off-by: Aviral Gupta <aviralg@codeaurora.org>