drivers/rtc: remove unnecessary semicolons

Found by Coccinelle: http://coccinelle.lip6.fr/



Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>