Log a copy of recovery log to kernel logs

Currently, recovery logs are only saved to /tmp/recovery.log . That's
bad, because /tmp/recovery.log would not be available after reboot. To
help debugging recovery issues, log a copy to kernel log, which will be
saved in pstore after device reboots.

Bug: 228893064
Change-Id: I0f97b402726ecabe644f3ff5182f71bd16d0b111