w1: gpio: Use sizeof(*pointer) instead of sizeof(type)

It is preferred to use sizeof(*pointer) instead of sizeof(type).
The type of the variable can change and one needs not change
the former (unlike the latter). No functional change intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20240307143644.3787260-4-andriy.shevchenko@linux.intel.com


Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>