Remove MySQL8-style obsolete markers

Author: ARitz-Cracker

tool/generate-error-constants.js

@@ -160,7 +160,8 @@ function extractMySqlVersion(srcDir) {
 function fixupCode(code) {
   return code
     // remove obsolete markers
-    .replace('ER_OBSOLETE_', 'ER_')
+    .replace(/^OBSOLETE_/, '')
+    .replace(/^ER_OBSOLETE_/, 'ER_')
     // remove unused markers
     .replace(/(?:_OLD)?_+UNUSED$/, '');
 }