fwts: add the Firmware Test Suite

The Firmware Test Suite is a set of tests for checking ACPI and EFI
implementations for common bugs and issues.

Signed-off-by: Fathi Boudra <fathi.boudra@linaro.org>
Signed-off-by: Graeme Gregory <graeme.gregory@linaro.org>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>