timerfd_tracker::fixup_after_fork_exec always tries to restore
the shared timer region at the same address as in the parent.
This is entirely unnecessary and wasn't intended, rather some
kind of copy/paste thinko. Fix that. Print NtMapViewOfSection
status code in api_fatal on failure for debugging.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>