protect eval-and-compile/eval-when-compile in let

hy/contrib/walk.hy

@@ -247,7 +247,11 @@ Arguments without a header are under None.
   (defn handle-call [self]
     (setv head (first self.form))
     (if (in head '[fn fn*]) (self.handle-fn)
-        (in head '[import require quote]) (self.handle-base)
+        (in head '[import
+                   require
+                   quote
+                   eval-and-compile
+                   eval-when-compile]) (self.handle-base)
         (= head 'except) (self.handle-except)
         (= head ".") (self.handle-dot)
         (= head 'defclass) (self.handle-defclass)