MAINTAINERS: Add entry for Analog Devices IIO drivers

Add Michael and myself as the maintainer for the Analog Devices IIO drivers.
The entry matches on all files in drivers/staging/iio and drivers/iio/ starting
with the 'ad' prefix, except for 'adjd' as that one is used by Avago
Technologies.

Signed-off-by: Lars-Peter Clausen <[e-mail]>
Signed-off-by: Jonathan Cameron <[e-mail]>

MAINTAINERS

···
 W:	http://blackfin.uclinux.org/
 S:	Supported
 F:	sound/soc/blackfin/*
+ 
+ANALOG DEVICES INC IIO DRIVERS
+M:	Lars-Peter Clausen <[e-mail]>
+M:	Michael Hennerich <[e-mail]>
+W:	http://wiki.analog.com/
+W:	http://ez.analog.com/community/linux-device-drivers
+S:	Supported
+F:	drivers/iio/*/ad*
+X:	drivers/iio/*/adjd*
+F:	drivers/staging/iio/*/ad*
+F:	staging/iio/trigger/iio-trig-bfin-timer.c
 
 AOA (Apple Onboard Audio) ALSA DRIVER
 M:	Johannes Berg <[e-mail]>