ss: Add a custom state value type

ss: Add a custom state value type

This patch just adds the type and updates all the switch cases.

It does nothing else for now, but it reduces the noise of the
other patch which actually adds the behavior of the custom value.

Change-Id: Ie16b2ff851968edc581f14abce175f0c0f2c6cc3
Signed-off-by: Genevieve Bastien <gbastien+lttng@versatic.net>
Reviewed-on: https://git.eclipse.org/r/70173
Reviewed-by: Hudson CI
Reviewed-by: Matthew Khouzam <matthew.khouzam@ericsson.com>
Tested-by: Matthew Khouzam <matthew.khouzam@ericsson.com>
Reviewed-by: Alexandre Montplaisir <alexmonthy@efficios.com>