libtuning: Remove the Cam object from ctt_awb.awb()

Replace the Cam object with a list parameter to be able to call the
ctt_awb.awb() function from libtuning code.

Signed-off-by: Stefan Klug <stefan.klug@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

utils/tuning/libtuning/ctt_awb.py

@@ -18,8 +18,7 @@ logger = logging.getLogger(__name__)
 """
 obtain piecewise linear approximation for colour curve
 """
-def awb(Cam, cal_cr_list, cal_cb_list, plot):
-    imgs = Cam.imgs
+def awb(imgs, cal_cr_list, cal_cb_list, plot):
     """
     condense alsc calibration tables into one dictionary
     """