media: sun8i-di: Fix coefficient writes

Currently coefficients are applied only once, since they don't change.
However, this is done before enable bit is set and thus it doesn't get
applied properly.

Fix that by applying coefficients after enable bit is set. While this
means that it will be done evey time, it doesn't bring much time
penalty.

Fixes: a4260ea4 ("media: sun4i: Add H3 deinterlace driver")
Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>