Fix (fake) repocop warning about unsafe usage /tmp/ usage

--- ./samples/debug-start.sh
+++ ./samples/debug-start.sh
@@ -1,9 +1,11 @@
 #!/bin/sh
 
-echo >>/tmp/ftp.proxy.log
-echo >>/tmp/ftp.proxy.log
-date >>/tmp/ftp.proxy.log
-echo >>/tmp/ftp.proxy.log
+LOG=$TMPDIR/ftp.proxy.log
 
-exec /usr/local/sbin/ftp.proxy -d -e -l 2>>/tmp/ftp.proxy.log
+echo >>$LOG
+echo >>$LOG
+date >>$LOG
+echo >>$LOG
+
+exec /usr/sbin/ftp.proxy -d -e -l 2>>$LOG