staging:iio:dac:ad5446: Add support for the AD5662

The AD5662 is compatible to the AD5660, but uses an external reference instead
of an internal.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/iio/dac/Kconfig

@@ -47,7 +47,7 @@ config AD5446
 	help
 	  Say yes here to build support for Analog Devices AD5444, AD5446,
 	  AD5512A, AD5542A, AD5543, AD5553, AD5601, AD5611, AD5620, AD5621,
-	  AD5640, AD5660 DACs.
+	  AD5640, AD5660, AD5662 DACs.
 
 	  To compile this driver as a module, choose M here: the
 	  module will be called ad5446.