With the new logic, the normal program flow runs until the end of
main(). Unfortunately, there is a `return(1);` at the end. Remove that.

We've seen deadlocks when mxqkill races with job completion.

Handle deadlocks errors in mysql_stmt_execute. This is possible, because
we don't start multi-statement transactions.

* fix-mysql-deadlock:
  my_myql: Handle deadlocks in mysql_stmt_execute