staging:iio:adc:ad7291: Fix typos, change kconfig description and file header

Make clear the AD7291 is primarily an ADC, and not a temp sensor.

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