IIO: Move the core files to drivers/iio

Take the core support + the kfifo buffer implentation out of
staging.  Whilst we are far from done in improving this subsystem
it is now at a stage where the userspae interfaces (provided by
the core) can be considered stable.

Drivers will follow over a longer time scale.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/iio/Makefile b/drivers/iio/Makefile
new file mode 100644
index 0000000..d5fc57d
--- /dev/null
+++ b/drivers/iio/Makefile
@@ -0,0 +1,10 @@
+#
+# Makefile for the industrial I/O core.
+#
+
+obj-$(CONFIG_IIO) += industrialio.o
+industrialio-y := industrialio-core.o industrialio-event.o inkern.o
+industrialio-$(CONFIG_IIO_BUFFER) += industrialio-buffer.o
+industrialio-$(CONFIG_IIO_TRIGGER) += industrialio-trigger.o
+
+obj-$(CONFIG_IIO_KFIFO_BUF) += kfifo_buf.o