fix tidy issue on file length

src/librustc_error_codes/error_codes.rs

@@ -1,3 +1,5 @@
+// ignore-tidy-filelength
+
 // Error messages for EXXXX errors.  Each message should start and end with a
 // new line, and be wrapped to 80 characters.  In vim you can `:set tw=80` and
 // use `gq` to wrap paragraphs. Use `:set tw=0` to disable.