Platform/Sgi: ACPI CPPC support for RD-V1 quad-chip platform

Enable ACPI CPPC mechanism for RD-V1 quad-chip platform as defined by
the ACPI specification. The implementation uses AMU registers accessible
as Fixed-feature Hardware (FFixedHW) for monitoring the performance.
Non-secure SCMI fastchannels are used to communicate with SCP to set the
desired performance. RD-V1 quad-chip platform does not support CPPC
revision 1 and below. So update the _OSC method to let OSPM know about
this fact.

Signed-off-by: Pranav Madhu <pranav.madhu@arm.com>
Reviewed-by: Thomas Abraham <thomas.abraham@arm.com>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>