media: videodev2.h: V4L2_DV_BT_BLANKING_HEIGHT should check 'interlaced'

If it is a progressive (non-interlaced) format, then ignore the
interlaced timing values.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Fixes: 7f68127f ([media] videodev2.h: defines to calculate blanking and frame sizes)
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>