Test: Add example partition for DMA-350 test

DMA-350 example partition demonstrates how to grant unprivileged tasks
access to DMA resources safely, using the checker layer service.

Signed-off-by: Gabor Abonyi <gabor.abonyi@arm.com>
Change-Id: I28bd37a998ad40102296bb132798ce3dc89f49cb
12 files changed