lxc: force kill of init process by sending SIGKILL if needed

Init process may remain after sending SIGTERM for some reason.
For example, if original init program is used, it is definitely
not killed by SIGTERM.

* src/lxc/lxc_controller.c: kill with SIGKILL if SIGTERM wasn't
  sufficient

src/lxc/lxc_controller.c

@@ -663,7 +663,11 @@ cleanup:
         close(containerPty);
 
     if (container > 1) {
+        int status;
         kill(container, SIGTERM);
+        if (!(waitpid(container, &status, WNOHANG) == 0 &&
+            WIFEXITED(status)))
+            kill(container, SIGKILL);
         waitpid(container, NULL, 0);
     }
     return rc;