drm/vc4: Disable the 2pixel/clock odd timings workaround for interlaced

Whilst BCM2712 does fix using odd horizontal timings, it doesn't
work with interlaced modes.

Drop the workaround for interlaced modes and revert to the same
behaviour as BCM2711.

https://github.com/raspberrypi/linux/issues/6281



Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>