MAINTAINERS: Add NXP S32 pinctrl maintainer and reviewer

Add myself as a maintainer and add NXP S32 Linux Team as a review group for
S32 pinctrl patches.

Signed-off-by: Chester Lin <clin@suse.com>
Link: https://lore.kernel.org/r/20230220023320.3499-4-clin@suse.com


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