msm: audio: qdsp6v2: disable read interrupts for smd channels

SMD channels are configured to send interrupts when the remote end
reads from the channels. Disable this behavior to reduce number
of interrupts.

CRs-Fixed: 578783
Change-Id: I5c46c263b81e70878fb6db587ac2aeb58b87c157
Signed-off-by: Haynes Mathew George <hgeorge@codeaurora.org>