refactor(cpus): use cpu errata wrappers for aarch64 hunter based cpus

Adapt to use errata frame-work cpu macro helpers for following cpus:

- cortex-a520
- cortex-a720
- cortex-x4
- cortex-chaberton
- cortex-blackhawk

- Use sysreg_bit_set helper macro for enabling of any system register
  bit field.
- Use errata_report_shim macro for reporting errata.
- Use cpu_reset_func_start/end helpers for adding cpu reset functions.

Testing:

- Manual comparison of disassembly with and without conversion.
- Using the test script in gerrit - 19136
- Building with erratas and stepping through from ArmDS and running tftf.

Change-Id: I954fb603aa3746e02f2288656b98148d9cfd7843
Signed-off-by: Govindraj Raja <govindraj.raja@arm.com>
5 files changed