soundwire: cadence_master: clear interrupt status before enabling interrupt

make sure all interrupts status are cleared before enabling interrupt
so that there is no unexpected interrupt triggered.

Signed-off-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200110215731.30747-3-pierre-louis.bossart@linux.intel.com


Signed-off-by: Vinod Koul <vkoul@kernel.org>