MAINTAINERS: fix typo in DRM DRIVER FOR SAMSUNG S6D27A1 PANELS

Commit ebd8cbf1 ("drm/panel: s6d27a1: Add driver for Samsung S6D27A1
display panel") introduces a new section DRM DRIVER FOR SAMSUNG S6D27A1
PANELS with a minor typo in one of its file entries.

Hence, ./scripts/get_maintainer.pl --self-test=patterns complains:

  warning: no file matches  F:  driver/gpu/drm/panel/panel-samsung-s6d27a1.c

So, repair the entry and make get_maintainer.pl happy.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210921122146.13132-1-lukas.bulwahn@gmail.com