hal: avoid stopping VoIP mistakenly when VoIP standby

When VoIP standby, VoIP usecase and TX device both are
disabled mistakenly. Then VoIP RX would maintain active
even if VoIP call disconnect. Because VoIP output still is
active, subsequent VoIP call cannot set up again.

Fix by avoid calling stop_input_stream() for compress voip
from in_standby().

CRs-Fixed: 2104812
Change-Id: I319da17f4f4e706f4aae240e6edb2539ac5cbad0