wsman-dispatcher: fix possible NULL dereference
wsman-dispatcher: fix possible NULL dereference

Check for NULL from:
ws_xml_get_node_text
list_create

Account for uri and action variables might be NULL:
In some context the uri and action variable cannot be NULL,
we should exit the flow.

Signed-off-by: Alexander Usyskin <2c2d03d7dae842f113743879f565d486184f22a3@intel.com>
Signed-off-by: Tomas Winkler <002a8af089113a6510dbc00453be711ac350fd80@intel.com>

vcrhonek/openwsman,vcrhonek/openwsman,kkaempf/openwsman,Openwsman/openwsman,vcrhonek/openwsman,Openwsman/openwsman,vcrhonek/openwsman,kkaempf/openwsman,vcrhonek/openwsman,Openwsman/openwsman,Openwsman/openwsman,vcrhonek/openwsman,kkaempf/openwsman,Openwsman/openwsman,kkaempf/openwsman,Openwsman/openwsman,kkaempf/openwsman,kkaempf/openwsman,kkaempf/openwsman,vcrhonek/openwsman,Openwsman/openwsman