drivers: media: imx477: Disable the scaler

The horizontal scaler was enabled for the 2028x1520 and 2028x1080 modes,
with a scale factor of 1. It caused a single column of bad pixels on the
right edge of the image. Since scaling is not needed for these modes,
disable it entirely.

Signed-off-by: Naushir Patuck <naush@raspberrypi.com>