soundwire: add read_ping_status helper definition in manager ops

soundwire: add read_ping_status helper definition in manager ops

The existing manager ops provide callbacks to transfer read/write
commands, but don't allow for direct access to PING status
register. This is accessible in all existing IP, and would help
diagnose timeouts or resume issues by reporting the 'true' status
instead of the internal status reported by the IP.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Acked-By: Vinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/20220714011043.46059-2-yung-chuan.liao@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>