Silence byte-compiler

Author: tarsius

rust-mode-treesitter.el

@@ -5,6 +5,9 @@
 
 ;;; Code:
 
+(defvar rust-before-save-hook)
+(defvar rust-after-save-hook)
+
 (when (version<= "29.1" emacs-version)
   ;; We have the when macro because of
   ;; https://github.com/rust-lang/rust-mode/issues/520