SL-11061 Viewer crashes on launch if serial is either unset or does not return a string

doc/contributions.txt

@@ -1073,6 +1073,7 @@ Nicky Dasmijn
 	MAINT-6665
 	SL-10291
 	SL-10293
+	SL-11061
 Nicky Perian
 	OPEN-1
 	STORM-1087

indra/newview/llmachineid.cpp

@@ -217,6 +217,13 @@ S32 LLMachineID::init()
 
             // Get the value of the Name property
             hr = pclsObj->Get(L"SerialNumber", 0, &vtProp, 0, 0);
+            if (FAILED(hr))
+            {
+                LL_WARNS() << "Failed to get SerialNumber. Error code = 0x" << hex << hres << LL_ENDL;
+                pclsObj->Release();
+                pclsObj = NULL;
+                continue;
+            }
             LL_INFOS("AppInit") << " Serial Number : " << vtProp.bstrVal << LL_ENDL;
 
             // use characters in the returned Serial Number to create a byte array of size len