ldconfig: dont run it if ldconfig is not installed
journal-remote: rename KEY_FILE to avoid confict with <linux/input.h>
bootchart: don't parse /proc/uptime, use CLOCK_BOOTTIME

* systemd-bootchart always parses /proc/uptime, although the
  information is unnecessary when --rel specified

* use /proc/uptime is overkill, since Linux 2.6.39 we have
  clock_gettime(CLOCK_BOOTTIME, ...). The backend on kernel side is
  get_monotonic_boottime() in both cases.

* main() uses "if (graph_start <= 0.0)" to detect that /proc is
  available.

  This is fragile solution as graph_start is always smaller than zero
  on all systems after suspend/resume (e.g. laptops), because in this
  case the system uptime includes suspend time and uptime is always
  greater number than monotonic time. For example right now difference
  between uptime and monotonic time is 37 hours on my laptop.

  Note that main() calls log_uptime() (to parse /proc/uptime) for each
  sample when it believes that /proc is not available. So on my laptop
  systemd-boochars spends all live with /proc/uptime parsing +
  nanosleep(), try

    strace  /usr/lib/systemd/systemd-bootchart

  to see the never ending loop.

  This patch uses access("/proc/vmstat", F_OK) to detect procfs.
bootchart: ask for --rel when failed to initialize graph start time

We always read system uptime before log start time. So the uptime
should be always smaller number, except it includes system suspend
time. It seems better to ask for --rel and exit() than try to be
smart and try to recovery from this situation or generate huge
messy graphs.