init: Delete /run/tmpfiles.log after including it in the syslog.

BUG=b:189503059
TEST=Check for /run/tmpfiles.log

Change-Id: I9ec24be7fb65fcc21becbc208694a0e52f74d85e
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform2/+/2950401
Tested-by: Allen Webb <allenwebb@google.com>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Commit-Queue: Allen Webb <allenwebb@google.com>
(cherry picked from commit f7a04643878e5106e2c30a8e5b02a5572e0aa8e7)
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform2/+/2952898
Reviewed-by: Kan Yan <kyan@google.com>
Reviewed-by: Allen Webb <allenwebb@google.com>
Tested-by: Kan Yan <kyan@google.com>
Auto-Submit: Kan Yan <kyan@google.com>
Commit-Queue: Kan Yan <kyan@google.com>
diff --git a/init/upstart/collect-early-logs.conf b/init/upstart/collect-early-logs.conf
index b394fc6..227c8a3 100644
--- a/init/upstart/collect-early-logs.conf
+++ b/init/upstart/collect-early-logs.conf
@@ -15,4 +15,5 @@
 script
   # Dump the log in syslog to preserve tmpfiles.d info over reboots.
   logger -t tmpfiles.d -f /run/tmpfiles.log || true
+  rm -f /run/tmpfiles.log
 end script