staging: iio: adc add numbers to naming of all adc channels as needed to associate...

staging: iio: adc add numbers to naming of all adc channels as needed to associate events with them.

Given event codes are associated by number not name, all adc channels
including those with names need to have numbers.

Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>