PM: EM: Implement em_notify_pd_created/updated()

PM: EM: Implement em_notify_pd_created/updated()

Implement two event notifications when a performance domain is created
(EM_CMD_PD_CREATED) and updated (EM_CMD_PD_UPDATED). The message format
of these two event notifications is the same as EM_CMD_GET_PD_TABLE --
containing the performance domain's ID and its energy model table.

Signed-off-by: Changwoo Min <changwoo@igalia.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/20251020220914.320832-10-changwoo@igalia.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>