media: platform: Add mali-c55 3a stats devnode

media: platform: Add mali-c55 3a stats devnode

Add a new code file to govern the 3a statistics capture node.

On ISP_START, fill the stats buffer by reading out the metering space
in the ISP's memory. This is done for the non-active config just as
the dma transfer of the registers is. To acheive that, move the
checking of the current config outside of mali_c55_swap_next_config()
so we can use it for both functions.

Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Acked-by: Nayden Kanchev  <nayden.kanchev@arm.com>
Co-developed-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Signed-off-by: Daniel Scally <dan.scally@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>
[hverkuil: remove deprecated vb2_ops_wait_prepare/finish callbacks]