drivers: media: imx477: Set horizontal binning when disabling the scaler

The horizontal scaler has been disabled but actually the sensor is not
binning horizontally, resulting in images that are stretched 2x
horizontally (missing the right half of the field of view completely).

Therefore we must additionally set the horizontal binning mode. There
is only marginal change in output quality and noise levels.

Signed-off-by: David Plowman <david.plowman@raspberrypi.com>
Fixes: f075893e ("drivers: media: imx477: Disable the scaler")