When mysqldadmin is run with sleep and count options,
it goes into an infinite loop and keeps executing the
specified command.

This happened because the statement, responsible for
decrementing the count value, was missing.

Fixed by adding a statement which will decrement the
count value for each iteration.


client/mysqladmin.cc:
  Bug#58221 : mysqladmin --sleep=x --count=x keeps looping
  
  Added a condition to check and decrement the count
  value stored in nr_iterations per iteration.
mysql-test/r/mysqladmin.result:
  Added a testcase for Bug#58221.
mysql-test/t/mysqladmin.test:
  Added a testcase for Bug#58221.