[$] Year-2038 work in 4.18

We now have less than 20 years to wait until the time_t value used
on 32-bit systems will overflow and create time-related mayhem across the
planet. The grand plan for solving this
problem was posted over three years ago now; progress since then has
seemed slow. But quite a bit of work has happened deep inside the kernel
and, in 4.18, some of the first work that will be visible to user space has
been merged. The year-2038 problem is not yet solved, but things are
moving in that direction.