pinctrl: sunxi: use kcalloc() instead of kzalloc()

Use devm_kcalloc() in init_pins_table() and prepare_function_table() to
gain built-in overflow protection, making memory allocation safer when
calculating allocation size compared to explicit multiplication.

Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Link: https://lore.kernel.org/20250819143935.372084-5-rongqianfeng@vivo.com


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>