tests: mem_protect/mem_protect: fix number of kobjects to test

In test_kobject_perm_error, there are 13 kobjects to test but
the loop only do 12. So amend the code to test all 13 kobjects.

Also remove the parameter of tid to child thread as the child
thread is not using it.

Signed-off-by: Daniel Leung <daniel.leung@intel.com>