soundwire: turn soundwire device off if device is down

When Soundwire master device down callback is called, rather
than calling device suspend, call device down and turn off
clock.

Change-Id: I0c9b2b5cd3b816a6bb840309c588e02cf5ebb7c8
Signed-off-by: Banajit Goswami <bgoswami@codeaurora.org>