cs: fix build with non-threaded scheme

racket/src/cs/demo/io.ss

@@ -135,6 +135,7 @@
 
    ;; ----------------------------------------
 
+   (when (threaded?)
      (let* ([place-symbols (make-hasheq)]
             [register-place-symbol!
              (lambda (sym proc)
@@ -164,7 +165,7 @@
              (place-channel-put pl f)
              (test (bytes-ref content 1) (place-channel-get pl))
              (test (bytes-ref content 2) (read-byte f))
-           (close-input-port f)))))
+             (close-input-port f))))))
 
    ;; Thread can be GCed if it's block on a place channel with no writer
    (let ()

racket/src/cs/rumble/lock.ss

@@ -47,7 +47,7 @@
   ;; engine-based concurrency
   (define-syntax-rule (with-global-lock e ...)
     (with-interrupts-disabled
-     e))]
+     e ...))]
  [else
   ;; Using a Chez Scheme build with thread support; make hash-table
   ;; access thread-safe at that level for `eq?`- and `eqv?`-based