leds: max5970: Remove unused variable

leds-max5970.c:50:21: warning: variable 'num_leds' set but not used [-Wunused-but-set-variable]

Remove unused variable.

Fixes: 736214b4 ("leds: max5970: Add support for max5970")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20231214184050.1272848-2-andriy.shevchenko@linux.intel.com


Signed-off-by: Lee Jones <lee@kernel.org>