soundwire: Remove cdns_master_ops

There can be instances where drivers using Cadence IP might want
to set sdw_master_ops differently per instance of it's use, so
remove the cdns_master_ops and export the APIs.

Signed-off-by: Shreyas NC <shreyas.nc@intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>