iio: Add IIO support for the DAC on the Apex Embedded Systems STX104

The Apex Embedded Systems STX104 is a 16-channel 16-bit analog input and
2-channel 16-bit analog output PC/104 card. The STX104 incorporates a
large one mega-sample FIFO.

This driver provides IIO support for the 2-channel DAC on the STX104.
The base port addresses for the devices may be configured via the "base"
module parameter array.

Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/MAINTAINERS b/MAINTAINERS
index 7c39a48..3cbff94 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -778,6 +778,12 @@
 S:	Maintained
 F:	sound/aoa/
 
+APEX EMBEDDED SYSTEMS STX104 DAC DRIVER
+M:	William Breathitt Gray <vilhelm.gray@gmail.com>
+L:	linux-iio@vger.kernel.org
+S:	Maintained
+F:	drivers/iio/dac/stx104.c
+
 APM DRIVER
 M:	Jiri Kosina <jikos@kernel.org>
 S:	Odd fixes