media: i2c: imx290: Support 60fps in 2 lane operation

Backport from https://patchwork.linuxtv.org/project/linux-media/list/?series=9918



Commit "97589ad6 media: i2c: imx290: Add support for 2 data lanes"
added support for running in two lane mode (instead of 4), but
without changing the link frequency that resulted in a max of 30fps.

Commit "98e0500e media: i2c: imx290: Add configurable link frequency
and pixel rate" then doubled the link frequency when in 2 lane mode,
but didn't undo the correction for running at only 30fps, just extending
horizontal blanking instead.

Remove the 30fps limit on 2 lane by correcting the register config
in accordance with the datasheet for 60fps operation over 2 lanes.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>