ASoC: da7219: Add entry to cover DA7219 bindings document

This adds an entry to indicate the DA7219 bindings document (and
other Dialog codecs bindings documents) are supported.
Signed-off-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

MAINTAINERS

@@ -3361,6 +3361,7 @@ M:	Support Opensource <support.opensource@diasemi.com>
 W:	http://www.dialog-semiconductor.com/products
 S:	Supported
 F:	Documentation/hwmon/da90??
+F:	Documentation/devicetree/bindings/sound/da[79]*.txt
 F:	drivers/gpio/gpio-da90??.c
 F:	drivers/hwmon/da90??-hwmon.c
 F:	drivers/iio/adc/da91??-*.c