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.

Change-Id: Idc6e57a68741dd6e52f0f1be57b8c85c586df59f
Signed-off-by: Panwar Vivek <vpanwa@codeaurora.org>