Cactus: Extend arguments in commands responses

In the test commands framework, added template to extend number of
values to include in a command response. This allows for a more
complete use of the available registers in direct message interfaces.

Signed-off-by: J-Alves <joao.alves@arm.com>
Change-Id: I34947f100c6322ca7319847cf44e844d63855c9d
2 files changed