rtc: mc13xxx: fix obfuscated and wrong format string

According to C99, %2.s means 'print two spaces' (a precision of
. without following digits or * means 0). The kernel's printf
implementation, however, treats that case as if no precision was
given, but relying on that quirk is rather silly. Also, since no -
(aka left-justify) flag is given, the field with of 2 would then cause
the alarm->enabled case to come out as "o n". Deobfuscate it.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>