This change adds a more informative error message in case of using airshipctl
with a Sushy emulator.
In the current implementation, by executing `airshipctl baremetal powerstatus`
command with invalid BMH configuration for example, returns:
redfish client encountered an error: BMC responded '500 INTERNAL SERVER ERROR'.
After this change the output looks like this:
redfish client encountered an error: BMC responded '500 INTERNAL SERVER ERROR'.
BMC responded: 'Error finding domain by name/UUID "air-ephemeral1" at libvirt
URI qemu:///system": Domain not found: no domain with matching name 'air-ephemeral1''
In case of using airshipctl with baremetal BMC, extendedInfo contains a valid
error message, so there are no issues.
Relates-To: #320
Change-Id: I437f50d5df4b0561f352804f269b0319badcc755
068718e07d