soundwire: bus: improve dynamic debug comments for enumeration

update comments to provide better understanding of enumeration flows.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20190806005522.22642-5-pierre-louis.bossart@linux.intel.com


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