This now accounts for system suspend periods on Linux, similar to how native win32 ticks work.
On macOS `mach_continuous_time` already does so.
~~On BSDs (and other POSIX compliant operating systems) `CLOCK_MONOTONIC` likewise includes suspend time. However they also provide a `CLOCK_BOOTTIME`, which does *not* include suspend time, hence the added `__linux__` check there.~~
See https://lkml.org/lkml/2020/5/8/1707
-- v2: ntdll: Switch to CLOCK_BOOTTIME for monotonic counters when available.