mod/scmi_clock: SCMI Notification enhancement in SCMI-clock

Current SCMI Notification which is implemented in SCMI layer has an
inherent limitation that it doesn't support custom notification
payload which is required when the agents have their own distinct
identification of the resources, i.e. SCMI clocks.

The new implementation has moved the SCMI notification processing
from SCMI to SCMI protocol layers so that each protocol can maintain
and customize its own notification table and payload, respectively.

Signed-off-by: Md Golam Tanvir Zim <mdgolamtanvir.zim@arm.com>
Change-Id: I0b11d6bc4dde0c8c148a4d274422ac11e753a781