SecurityPkg/Test: add AARCH64 to host test DSC Add AARCH64 to SUPPORTED_ARCHITECTURES so the SecurityPkg host-based unit tests build and run on an AARCH64 host. Depends on the AARCH64 host-test framework enablement (UnitTestFrameworkPkg/MdePkg). Signed-off-by: Jeff Brasen <jbrasen@nvidia.com>