backlight: s6e63m0: use lowercase names of structs

Lowercase names of structs should be used, because they are
not preprocessor macros.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>