sysupgrade: do not kill any processes in failsafe

sysugrade killed the lock causing failsafe to stop

Signed-off-by: Alexander Couzens <lynxis@fe80.eu>

SVN-Revision: 39318

package/base-files/files/sbin/sysupgrade

@@ -210,9 +210,11 @@ run_hooks "" $sysupgrade_pre_upgrade
 ubus call system upgrade
 touch /tmp/sysupgrade
 
-kill_remaining TERM
-sleep 3
-kill_remaining KILL
+if [ ! -f /tmp/failsafe ] ; then
+	kill_remaining TERM
+	sleep 3
+	kill_remaining KILL
+fi
 
 if [ -n "$(rootfs_type)" ]; then
 	v "Switching to ramdisk..."