coresight-tpdm: Add nodes to set trigger timestamp and type

The nodes are needed to set or show the trigger timestamp and
trigger type. This change is to add these nodes to achieve these
function.

Signed-off-by: Tao Zhang <quic_taozha@quicinc.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/1695882586-10306-8-git-send-email-quic_taozha@quicinc.com