Various fixes following a code review

Various fixes following a code review

* src/libvirt.c src/lxc/lxc_conf.c src/lxc/lxc_container.c
  src/lxc/lxc_controller.c src/node_device/node_device_hal.c
  src/openvz/openvz_conf.c src/qemu/qemu_driver.c
  src/qemu/qemu_monitor_text.c src/remote/remote_driver.c
  src/storage/storage_backend_disk.c src/storage/storage_driver.c
  src/util/logging.c src/xen/sexpr.c src/xen/xend_internal.c
  src/xen/xm_internal.c: Steve Grubb <sgrubb@redhat.com> sent a code
  review and those are the fixes correcting the problems