org-compat.el: org-export-babel-evaluate is an obsolete variable

* lisp/org-compat.el (org-export-babel-evaluate) is marked as an
  obsolete variable.  It was marked as a function.

lisp/org-compat.el

@@ -191,7 +191,7 @@ Counting starts at 1."
 (define-obsolete-variable-alias 'org-html-style 'org-html-head "24.4")
 (define-obsolete-function-alias 'org-insert-columns-dblock
   'org-columns-insert-dblock "Org 9.0")
-(define-obsolete-function-alias 'org-export-babel-evaluate
+(define-obsolete-variable-alias 'org-export-babel-evaluate
   'org-export-use-babel "Org 9.1")
 
 (defun org-in-fixed-width-region-p ()