build-acs: add a component build script to build Arm ACS

Arm ACS is a test suite used to ensure that a server platform adheres to
Arm's SBSA and SBBR specifications. Add a component build script to build
Arm ACS test suite.

Change-Id: I01f45e1596592d7f1e182aeea3536ca702ec11ed
Signed-off-by: Thomas Abraham <thomas.abraham@arm.com>