rtc: s3c: Minor white-space cleanups

Minor cleanups to make the code easier to read. No functional changes.
1. Remove one space before labels as this is nowadays mostly preferred.
2. Fix indentation of arguments in function calls.
3. Split structure member declaration.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>