change "next" to "done" in minute IME option under 24-hour format

We don't need "next" button under 24-hour format any more.
So, we changed from "next" button to "done" in IME option
when setting minute under 24-hour format

AOSP commit: https://android-review.googlesource.com/#/c/54121/3

Change-Id: Ic9b1673248183060ba7279b63648a85dc39ca3b9