media: hantro: Set H264 FIELDPIC_FLAG_E flag correctly

The FIELDPIC_FLAG_E bit should be set when field_pic_flag exists in stream,
it is currently set based on field_pic_flag of current frame.
The PIC_FIELDMODE_E bit is correctly set based on the field_pic_flag.

Fix this by setting the FIELDPIC_FLAG_E bit when frame_mbs_only is not set.

Fixes: dea0a82f ("media: hantro: Add support for H264 decoding on G1")
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>