leds: tca6507: Don't use fixed GPIO base

First of all, the fixed GPIO base is source of troubles and
it doesn't scale. Second, there is no in-kernel user of this
base, so drop it.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20231002135629.2605462-1-andriy.shevchenko@linux.intel.com


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