staging:iio:adc:ad799x trivial: use the convenient chan struct.

This is much cleaner than bouncing through the various structures
to get to the same thing.

Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
1 file changed