rtc: remove duplicated words in comments

Signed-off-by: shaomin Deng <dengshaomin@cdjrlc.com>
Link: https://lore.kernel.org/r/20220808152354.3641-1-dengshaomin@cdjrlc.com
Link: https://lore.kernel.org/r/20220808153454.6844-1-dengshaomin@cdjrlc.com
Link: https://lore.kernel.org/r/20220808152822.5012-1-dengshaomin@cdjrlc.com


Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>