8261154: Memory leak in Java_java_lang_ClassLoader_defineClass0 with long class names

Reviewed-by: stuefe, chegar, mchung

src/java.base/share/native/libjava/ClassLoader.c

@@ -262,6 +262,9 @@ Java_java_lang_ClassLoader_defineClass0(JNIEnv *env,
 
     result = JVM_LookupDefineClass(env, lookup, utfName, body, length, pd, initialize, flags, classData);
 
+    if (utfName && utfName != buf)
+        free(utfName);
+
  free_body:
     free(body);
     return result;