media: ti-vpe: cal: cleanup phy iteration in cal_remove

Most of the driver has moved from ARRAY_SIZE(cal->phy) to
cal->data->num_csi2_phy, but we have one place left in cal_remove. Also,
checking for cal->phy[i] != NULL is not needed as we always have all the
phys instantiated.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>