MDEV-17068 mysql system table is marked as crashed and should be repaired after the server crashes or is killed

- Changed ERROR to WARNING for MyISAM/Aria message
  that are warnings in the check utilities.
  This affects for example "client is using or
  hasn't closed the table properly".
- Print "Table is fixed" if check succeded in
  fixing the table.

sql/sql_class.h

@@ -3123,6 +3123,9 @@ public:
     it returned an error on master, and this is OK on the slave.
   */
   bool       is_slave_error;
+  /* True if we have printed something to the error log for this statement */
+  bool       error_printed_to_log;
+
   /*
     True when a transaction is queued up for binlog group commit.
     Used so that if another transaction needs to wait for a row lock held by