mod_perf_controller: Rename perf controller blocks.

The renaming was carried out as perf controller use cases grow larger, its components names need to be renamed to adapt to the new use cases. The blocks core and cluster would be renamed limiter and controller domain to avoid confusion and to be more generic.

The controller domain in the system consists of various performance limiters and applies the lowest performance limit across the domain.

Signed-off-by: Mahmoud Elsabbagh mahmoud.elsabbagh@arm.com