lava_helper: initial support QEMU MPS2

Add an initial configuration for lava job generator and a jinja2 template,
to support MPS2 platform under QEMU. Validated job [1].

[1] https://tf.validation.linaro.org/scheduler/job/30217

Signed-off-by: Leonardo Sandoval <leonardo.sandoval@linaro.org>
Change-Id: Iaee1543403fb641596f8afd8ad0f59b39882bb0a
2 files changed