media: rkvdec: Fix frame size enumeration

The VIDIOC_ENUM_FRAMESIZES ioctl should return all frame sizes (i.e.
width and height in pixels) that the device supports for the given pixel
format.

It doesn't make a lot of sense to return the frame-sizes in a stepwise
manner, which is used to enforce hardware alignments requirements for
CAPTURE buffers, for coded formats.

Instead, applications should receive an indication, about the maximum
supported frame size for that hardware decoder, via a continuous
frame-size enumeration.

Fixes: cd33c830 ("media: rkvdec: Add the rkvdec driver")
Suggested-by: Alex Bee <knaerzche@gmail.com>
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>