Add init test with different runlevels and test for management device status

Signed-off-by: Katarzyna Lapinska <katarzyna.lapinska@intel.com>

test/functional/api/cas/cas_module.py

@@ -4,7 +4,7 @@
 #
 
 from aenum import Enum
-
+from core.test_run import TestRun
 from test_utils import os_utils
 from test_utils.os_utils import ModuleRemoveMethod
 
@@ -24,3 +24,7 @@ def unload_all_cas_modules():
                                   os_utils.ModuleRemoveMethod.rmmod)
     os_utils.unload_kernel_module(CasModule.disk.value,
                                   os_utils.ModuleRemoveMethod.rmmod)
+
+
+def is_cas_management_dev_present():
+    return TestRun.executor.run("test -c /dev/cas_ctrl").exit_code == 0