Issue an error if user specifies multiple commands to run.
        Also there was an unnoticed bug that DO_CHECK was actually 0 which lead
        to wrong actions in some cases.
        The mysqlcheck.test contained commands with the suspicious meaning
        for the above reason. Extra commands removed from there.

per-file commands:
  client/mysqlcheck.c
Bug#35269      mysqlcheck behaves different depending on order of parameters
        Drop with an error if multiple commands.
  mysql-test/r/mysqlcheck.result
Bug#35269      mysqlcheck behaves different depending on order of parameters
        result completed.
  mysql-test/t/mysqlcheck.test
Bug#35269      mysqlcheck behaves different depending on order of parameters
        testcase added.
        not-working commands removed from some mysqlcheck calls.