iio: light: Add support for Capella CM3323 color sensor

Minimal implementation providing raw light intensity
and integration time attribute.

Userspace applications can use GREEN channel for raw
illuminance readings following this table:

Integration Time | G Sensitivity
================================
40 ms            | 0.18
80 ms            | 0.09
160 ms           | 0.045
320 ms           | 0.0225
640 ms           | 0.01125
1280 ms          | 0.005625

Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/iio/light/Makefile

@@ -8,6 +8,7 @@ obj-$(CONFIG_AL3320A)		+= al3320a.o
 obj-$(CONFIG_APDS9300)		+= apds9300.o
 obj-$(CONFIG_CM32181)		+= cm32181.o
 obj-$(CONFIG_CM3232)		+= cm3232.o
+obj-$(CONFIG_CM3323)		+= cm3323.o
 obj-$(CONFIG_CM36651)		+= cm36651.o
 obj-$(CONFIG_GP2AP020A00F)	+= gp2ap020a00f.o
 obj-$(CONFIG_HID_SENSOR_ALS)	+= hid-sensor-als.o