CMA test driver for snowball (patch, doc and LAVA)

Hello,

I have wrote a test for CMA, it use a board specific driver in association with a script in userland. This test allow us to test buffer allocation/release on snowball.

The test is now running (locally) on LAVA.

I have put more documentation, patches and LAVA test description here : https://wiki.linaro.org/OfficeofCTO/MemoryManagement/Validation/CMATest

The blueprint for this stuff is: https://blueprints.launchpad.net/linaro-mm-sig/+spec/engr-umm-cma-debug

Next steps are: - run this test on LAVA farm boards. - write test drivers for other boards.

Regards, Benjamin