container: Add mmtests benchmark suite

Create a container that can run any benchmark integrated into the
mmtests suite.

An optional "base config" (a pre-canned mmtests config file) can be
provided as well as an optional "config" which is overlaid on top of the
base. Both of these are provided via the fastpath benchmark params. This
approach allows for running standard mmtests configs, customising
standard mmtests configs, and running a completely custom config.

Additionally, the user can specify whether to force the performance
governor via params.

The container can automatically extract all required information from
the results and format it into the standard fastpath results format.

Signed-off-by: Ryan Roberts