sysklogd: upgrade 2.5.0 -> 2.5.2

sysklogd: upgrade 2.5.0 -> 2.5.2

Changelog:
- Issue #67: restore support for reading kernel logs from '/proc/kmsg',
  regression introduced in v2.4.0, issue #48.
- Issue #37: improved accuracy of the MARK timer, optional, default: 20
  minutes.  Generates log messages to files, which have had no activity
  within the MARK interval.  Was off by up to 'interval / 2' minutes.
  It may now be off by up to '1 / 2' minutes, i.e.g, 30 seconds.
- Issue #64: sub-second faking of kernel timestamps was always zero

Signed-off-by: Wang Mingyu <wangmy@fujitsu.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>