coresight: Change name of pdata->conns

conns is actually for output connections. Change the name to make it
clearer and so that we can add input connections later.

No functional changes.

Reviewed-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: James Clark <james.clark@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20230425143542.2305069-4-james.clark@arm.com