video: ipuv3: imx-ldb: Support video modes in ldb node
We used to support video modes directly in the ldb device node, that
was lost in: 5bda17e video: ipuv3: Replace ipu_output with VPL.
Add this support back. Also drop duplicate vpl ioctl forwarding for
several calls.
With this patch modes can either be retrieved from the ldb node as
originally done or from the panel remote port.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>