added InSystemModule for hti.nim

lib/system.nim

@@ -47,6 +47,8 @@ const
 
 {.push hints: off.}
 
+const InSystemModule = true
+
 type
   Ordinal* {.magic: Ordinal.}[T]
   `nil` {.magic: "Nil".}

lib/system/hti.nim

@@ -7,8 +7,7 @@
 #    distribution, for details about the copyright.
 #
 
-when defined(NimString): 
+when defined(InSystemModule): 
-  # we are in system module:
   {.pragma: codegenType, compilerproc.}
 else:
   {.pragma: codegenType.}