iio: light: cm3232: move calibscale to struct cm3232_chip

Move the calibscale field from struct cm3232_als_info to struct
cm3232_chip. The chip info struct is supposed to be const while the
driver data struct should contain mutable fields. Since calibscale
is a mutable field, it should be in the driver data struct.

Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://patch.msgid.link/20250628-iio-const-data-20-v1-1-2bf90b03f9f1@baylibre.com


Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>