iio:adis16400: Expose some debug information in debugfs

Expose some information useful for debugging a device in debugfs. This includes
for now the flash count, the product id and the serial number and raw register
access.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2 files changed