removed modification of org-babel-load-languages

* lisp/ob-C.el: Don't modify `org-babel-load-languages' from ob-* files.

lisp/ob-C.el

@@ -39,8 +39,6 @@
 
 (defvar org-babel-tangle-lang-exts)
 (add-to-list 'org-babel-tangle-lang-exts '("C++" . "cpp"))
-(let ((x (member '(C . t) org-babel-load-languages)))
-  (setcdr x  (cons '(C++ . t) (subseq x 1))))
 
 (defvar org-babel-default-header-args:C '())