totalcompute/tc4: Introduce TC24

* Add initial TC4 implementation based on TC3.
* TC4 has a single-stage boot. This commit combines TC3 boot stages
  into a single one.
* Add ATU platform support.
* Set the primary cluster and core to be powered by power domain.
  This makes all the cores to be aligned, as all the other cores
  are powered by power domain as well.
* Combine scp_boot and scp_runtime transport config files from TC3
  into a single config file for TC4.
* Combine scp_boot and scp_runtime mhu3 config files from TC3 into a
  single config file for TC4.
* Add core/cluster macros. There is no need for these values to be
  determined via inline functions and indeed doing so prevents static
  initialisation.

Co-developed-by: Boyan Karatotev <boyan.karatotev@arm.com>
Co-developed-by: Jackson Cooper-Driver <jackson.cooper-driver@arm.com>
Co-developed-by: Tintu Thomas <tintu.thomas@arm.com>
Co-developed-by: Jing Han <jing.han@arm.com>
Signed-off-by: Noe Galea-Sevilla <noe.galea-sevilla@arm.com>
Signed-off-by: Vishnu Banavath <vishnu.banavath@e131718.arm.com>