Checkmk Werk 12216: agent_vsphere: Fix compatibility for version 5.5

ID: 12216 Title: agent_vsphere: Fix compatibility for version 5.5 Component: Checks & agents Level: 1 Class: Bug fix Version: 2.1.0i1 The connection to an ESX with version 5.5 resulted in the error "Cannot login to vSphere Server (reason: [200] OK). Please check the credentials." even if the credentials were correct.