This change implements platform services for stm32mp1 to expose clock
and reset controllers over SCMI clock and reset domain protocols
in sp_min firmware.

Requests execution use a fastcall SMC context using a SiP function ID.
The setup allows the create SCMI channels by assigning a specific
SiP SMC function ID for each channel/agent identifier defined. In this
change, stm32mp1 exposes a single channel and hence expects single
agent at a time.

The input payload in copied in secure memory before the message
in passed through the SCMI server drivers. BL32/sp_min is invoked
for a single SCMI message processing and always returns with a
synchronous response message passed back to the caller agent.

This change fixes and updates STM32_COMMON_SIP_NUM_CALLS that was
previously wrongly set 4 whereas only 1 SiP SMC function ID was to
be counted. STM32_COMMON_SIP_NUM_CALLS is now set to 3 since the
2 added SiP SMC function IDs for SCMI services.

Change-Id: Icb428775856b9aec00538172aea4cf11e609b033
Signed-off-by: Etienne Carriere <etienne.carriere@st.com>