leds: is31fl319x: use simple i2c probe function

The i2c probe functions here don't use the id information provided in
their second argument, so the single-parameter i2c probe function
("probe_new") can be used instead.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vincent Knecht <vincent.knecht@mailoo.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>