Make the documentation on how to write and port i2c drivers more in
line with the current state of things:
* i2c-isa is deprecated and soon gone, so stop advertising it.
* Drop many sensors-specific references. Most of them were outdated
anyway.
* Update the example code to reflect the recent and not-so-recent
API and coding style preference changes.
* Simplify the example init and cleanup functions.
This should make things less complex to understand for newcomers.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
eefcd75e72