ASoC: msm: qdsp6v2: Don't request to open irrelevant SMD channels

APSS is unable to open apr_voice_svc channel with destination processor
as MODEM. This is due to MODEM is no longer opening that channel, also
none of the clients on apps are using this channel. Hence, don't request
for the SMD channels when the destination is MODEM, but ensure that apr
clients should be able to receive SSR notifications from MODEM subsystem.

Change-Id: I566dd065ccd75956ab8fd594bb94e09b699258dd
Signed-off-by: Venkata Narendra Kumar Gutta <vgutta@codeaurora.org>