[media] st-delta: STiH4xx multi-format video decoder v4l2 driver

This V4L2 driver enables DELTA multi-format video decoder
of STMicroelectronics STiH4xx SoC series.

Acked-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Hugues Fruchet <hugues.fruchet@st.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>