updated for version 7.3.1149

Problem:    New regexp engine: Matching plain text could be faster.
Solution:   Detect a plain text match and handle it specifically.  Add
            vim_regfree().

src/edit.c

@@ -3134,7 +3134,7 @@ ins_compl_dictionaries(dict_start, pat, flags, thesaurus)
 
 theend:
     p_scs = save_p_scs;
-    vim_free(regmatch.regprog);
+    vim_regfree(regmatch.regprog);
     vim_free(buf);
 }