Documentation: coresight: Link config options to existing documentation

Documentation: coresight: Link config options to existing documentation

In order to document the newly added branch_broadcast option, create a
table that links all of the config option formats to any existing docs.
That way when the branch broadcast docs are expanded they are accessible
from both places.

Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20220511144601.2257870-4-james.clark@arm.com