doc: Add the remaining Use-Cases to the Reproduce page

Add brief sections for the remaining use-cases to the "Reproducing the
Use-Cases" section on the Reproduce page:

 * Arm SystemReady IR Firmware Build
 * Arm SystemReady IR Architecture Compliance Suite (ACS) Tests
 * Linux Distribution Installation (Debian and Fedora)

The latter two link to the existing Arm SystemReady IR Validation
section.

Signed-off-by: Peter Hoyes <Peter.Hoyes@arm.com>