media: platform: exynos4-is: remove all references to physical addresses

This driver always operates on the DMA/IOVA addresses, so calling them
physical addresses is misleading, although when no IOMMU is used they
equal each other. Fix this by renaming all such entries to 'addr' and
adjusting comments.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>