Don't warn on missing dmidecode
Don't warn on missing dmidecode

Missing dmidecode is only relevant for RSD backend, but the warning will
appear on all systems since this is logged on the get_connector_properties.

We don't really need dmidecode to get the UUID, we can just go and read
the contents of /sys/class/dmi/id/product_uuid

To better support systems that don't have dmidecode in the system, we
will check sysfs first, and then try dmidecode (in case it covers some
additional cases), and log it as a debug level message if dmidecode is
not present.

Closes-Bug: #1811822
Change-Id: Ibfaed6503bd91ad64987deecdc2e9a1471441005

openstack/os-brick,openstack/os-brick