Round the time-to-next-alarm up for display in the toast

The old code rounded downward which gave puzzling results.

e.g. time is 7:00:14 (14 seconds after 7 o'clock).
Set alarm for 8:00.
Toast says "Alarm set for 59 minutes from now."

The toast will now say "Alarm set for 1 hour from now."

Bug: 6809304
Change-Id: Ib742974ed720fa380ac935dcb45746b64c13c94c