dt-bindings: iio: adc: Add docs for ad7124

Add support for Analog Devices AD7124 4-channels and 8-channels ADC.

Signed-off-by: Stefan Popa <stefan.popa@analog.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
diff --git a/MAINTAINERS b/MAINTAINERS
index 457f29b..1fe69e3 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -845,6 +845,7 @@
 W:	http://ez.analog.com/community/linux-device-drivers
 S:	Supported
 F:	drivers/iio/adc/ad7124.c
+F:	Documentation/devicetree/bindings/iio/adc/adi,ad7124.txt
 
 ANALOG DEVICES INC AD9389B DRIVER
 M:	Hans Verkuil <hans.verkuil@cisco.com>