MAINTAINERS: Add MAINTAINERS entry for AD7091R

The driver for AD7091R was added in
ca693001: iio: adc: Add support for AD7091R5 ADC
but no MAINTAINERS file entry was added for it since then.
Add a proper MAINTAINERS file entry for the AD7091R driver.
Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
Link: https://lore.kernel.org/r/4247e653354f8eb362264189db24c612d5e4e131.1703013352.git.marcelo.schmitt1@gmail.comSigned-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

MAINTAINERS

@@ -1122,6 +1122,14 @@ F:	Documentation/ABI/testing/sysfs-bus-iio-adc-ad4130
 F:	Documentation/devicetree/bindings/iio/adc/adi,ad4130.yaml
 F:	drivers/iio/adc/ad4130.c
 
+ANALOG DEVICES INC AD7091R DRIVER
+M:	Marcelo Schmitt <marcelo.schmitt@analog.com>
+L:	linux-iio@vger.kernel.org
+S:	Supported
+W:	http://ez.analog.com/community/linux-device-drivers
+F:	Documentation/devicetree/bindings/iio/adc/adi,ad7091r*
+F:	drivers/iio/adc/drivers/iio/adc/ad7091r*
+
 ANALOG DEVICES INC AD7192 DRIVER
 M:	Alexandru Tachici <alexandru.tachici@analog.com>
 L:	linux-iio@vger.kernel.org