Bug#44394 Assertion Failure

  the problem is in the TIMESTAMP(14) fields of the access-control tables.
  The TIMESTAMP(14) syntax is marked as DEPRECATED since 5.2.
  Fixed by just changed the check to 6.0 as it's done in the 5.1 branch.
      
per-file comments:
  sql/sql_parse.cc
Bug#44394      Assertion Failure
    now it's deprecated since 6.0

sql/sql_parse.cc

@@ -6038,7 +6038,7 @@ bool add_field_to_list(THD *thd, LEX_STRING *field_name, enum_field_types type,
     */
     char buf[32];
     my_snprintf(buf, sizeof(buf), "TIMESTAMP(%s)", length);
-    WARN_DEPRECATED(thd, "5.2", buf, "'TIMESTAMP'");
+    WARN_DEPRECATED(thd, "6.0", buf, "'TIMESTAMP'");
   }
 
   if (!(new_field= new Create_field()) ||