refactor(neoverse-rd): refactor nrd_soc_platform_def_v2.h file

Continuing the refactoring of the various definitions for the second
generation platforms based on the N2/V2 CPU, refactor the definitions in
the nrd_soc_platform_def_v2.h file into the following files as
appropriate.

- nrd_ros_def2.h: includes RoS hardware related definitions
- nrd_ros_fw_def2.h: includes RoS firmware related definitions
- nrd_plat_arm_def2.h: includes platform port related definitions

RoS (Rest Of System) is used to refer to the part of the reference
design platform that excludes CSS. The file inclusions in the
platform_def.h file of the platforms have been updated accordingly.

Signed-off-by: Rohit Mathew <rohit.mathew@arm.com>
Change-Id: I393e6f4a84be45f1781ea281bd55fa813803f6db
6 files changed