media: i2c: ks0127: remove unused struct 'adjust'

'adjust' has been unused since original
commit fbe60daa ("V4L/DVB (3916): AverMedia 6 Eyes AVS6EYES
support").

Remove it.

Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>