Add autoload magic comments for the functions exposed by google-c-style.

This should make packaged versions of google-c-style (like from MELPA)
provide the symbols without doing explicit 'require.

Patch by Kimmo Kinnunen <kkinnunen@nvidia.com>.
diff --git a/google-c-style.el b/google-c-style.el
index ffa58aa..9bb12c6 100644
--- a/google-c-style.el
+++ b/google-c-style.el
@@ -64,6 +64,7 @@
       (goto-char (match-end 0))))
     (vector (+ 4 (current-column)))))
 
+;;;###autoload
 (defconst google-c-style
   `((c-recognize-knr-p . nil)
     (c-enable-xemacs-performance-kludge-p . t) ; speed up indentation in XEmacs
@@ -129,6 +130,7 @@
                         (innamespace . 0))))
   "Google C/C++ Programming Style.")
 
+;;;###autoload
 (defun google-set-c-style ()
   "Set the current buffer's c-style to Google C/C++ Programming
   Style. Meant to be added to `c-mode-common-hook'."
@@ -137,6 +139,7 @@
   (setq c-tab-always-indent t)
   (c-add-style "Google" google-c-style t))
 
+;;;###autoload
 (defun google-make-newline-indent ()
   "Sets up preferred newline behavior. Not set by default. Meant
   to be added to `c-mode-common-hook'."