fix: read a Supermicro X10 with only the OOB license over Redfish (0.3.1)

First run against real hardware over Redfish: an X10DRL-i (BMC 3.91) with
SFT-OOB-LIC. Its Redfish tree is recorded under
tests/fixtures/supermicro-x10drl-i-3.91/redfish, scrubbed.

- A resource refused for want of a further license (403 OemLicenseNotPassed)
  no longer fails the getter. Storage then falls back to SimpleStorage. The
  firmware list falls back to the BMC and BIOS versions when UpdateService
  is withheld.
- get_device_warnings reports bmc_license_partial with the licenses and the
  withheld parts (drives, firmware inventory).
- A placeholder system model ("Super Server") is replaced by the board
  (PartNumber, else the chassis model).

tests/fixtures/supermicro-x10drl-i-3.91/redfish/Systems/1/Memory/7/index.json

@@ -0,0 +1,35 @@
+{
+ "@odata.context": "/redfish/v1/$metadata#Memory.Memory",
+ "@odata.id": "/redfish/v1/Systems/1/Memory/7",
+ "@odata.type": "#Memory.v1_1_0.Memory",
+ "AllowedSpeedsMHz": [
+  2133
+ ],
+ "BusWidthBits": 72,
+ "CapacityMiB": 16384,
+ "DataWidthBits": 64,
+ "Description": "Memory",
+ "DeviceLocator": "P2-DIMMG1",
+ "Id": "7",
+ "Manufacturer": "Samsung",
+ "MemoryDeviceType": "DDR4",
+ "MemoryLocation": {
+  "Channel": 2,
+  "MemoryController": 1,
+  "Slot": 0,
+  "Socket": 1
+ },
+ "MemoryMedia": [
+  "DRAM"
+ ],
+ "MemoryType": "DRAM",
+ "Name": "P2-DIMMG1",
+ "OperatingSpeedMhz": 1866,
+ "PartNumber": "M393A2G40DB0-CPB",
+ "RankCount": 7,
+ "SerialNumber": "SN00000008",
+ "Status": {
+  "Health": "OK",
+  "State": "Enabled"
+ }
+}