mod/power_capping_hal: Add power notifications and threshold support
Implement support in the Power capping HAL for sending notifications:
- When the power averaging interval (PAI) changes.
- When the average power consumption of the power capping domain, measured over PAI, is outside the threshold values set by the agent for the power capping domain.
Also add support for setting low/high power thresholds using mod_pcapping_set_power_thresholds(), which allows agents to define when measurement-based notifications should occur for the power capping domain.
Update scmi_power_capping to allow agents to subscribe to and process these new notifications.
Signed-off-by: Mahmoud Elsabbagh mahmoud.elsabbagh@arm.com