media: hantro: h264: Move DPB valid and long-term bitmaps

In order to reuse these bitmaps, move this process to
struct hantro_h264_dec_hw_ctx. This will be used by
the Rockchip VDPU2 H.264 driver.

This idea was originally proposed by Jonas Karlman
in "[RFC 08/12] media: hantro: Fix H264 decoding of field encoded content"
which was posted a while ago.

Link: https://lore.kernel.org/linux-media/HE1PR06MB4011EA39133818A85768B91FACBF0@HE1PR06MB4011.eurprd06.prod.outlook.com/



Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Tested-by: Alex Bee <knaerzche@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>