kernel/time/Kconfig: Fix typo in comment

Fix typo in Kconfig comment text.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Jiri Kosina <trivial@kernel.org>
Link: https://lkml.kernel.org/r/0e586dd4-2b27-864e-c252-bc72df52fd01@infradead.org