rewrite Get Device GUID to use new provider API

Modify to use the new provider API. One by one, change calls to
remove any legacy API constructs.

Tested-by: ipmitool 6 8
            30 ba 05 cd 7e 9d ac 89 4a 4c 52 ef f3 24 2d 5f
           (with matching change from bmcweb:)
           curl https://<bmcip>/redfish/v1/Managers/bmc
           ...
               "UUID": "5f2d24f3-ef52-4c4a-89ac-9d7ecd05ba30"

Change-Id: I4cd3b945f76b4fe6c4fcf31d8e1962aaa768828e
Signed-off-by: Vernon Mauery <vernon.mauery@linux.intel.com>
1 file changed