[media] tvp5150: fix pad format frame height

Even if field order is set to V4L2_FIELD_ALTERNATE, the width and height
values in struct v4l2_mbus_framefmt still refer to frame size, not field
size.

Fixes: 4f57d27b ("[media] tvp5150: fix tvp5150_fill_fmt()")

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>