ARM: s3c64xx: Delete an unnecessary return statement in samsung_bl_set

Fix checkpatch warning:
	WARNING: void function return statements are not generally useful

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
[krzk: Rewrite commit message]
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>