ASoC: compress: Fix compress capture stream handling

Compress framework considers the stream as PLAYBACK
always irrespective of the direction.
Derive substream based on the tx/rx direction from
compressed stream.

CRs-fixed: 1072067
Change-Id: I62c51c23a47f26b221dccef6f83c03aef9f095a7
Signed-off-by: Satish Babu Patakokila <sbpata@codeaurora.org>