hwmon: Remove many EXPERIMENTAL flags

Remove the dependency on EXPERIMENTAL for all drivers which are in
the kernel tree for a long time, are known to work properly and for
which we have documentation.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Corentin Labbe <corentin.labbe@geomatys.fr>
Cc: Riku Voipio <riku.voipio@iki.fi>
Cc: Juerg Haefliger <juergh@gmail.com>
Acked-by: Guenter Roeck <guenter.roeck@ericsson.com>