pinctrl: MAINTAINERS: Drop bouncing Jianlong Huang

Emails to Jianlong Huang bounce since 9 months, so drop the person from
maintainers:

  550 5.4.1 Recipient address rejected: Access denied.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/20250528104514.184122-2-krzysztof.kozlowski@linaro.org


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