Dont call UNIMPLEMENTED for 'empty services', just return error code

src/core/hle/service/sm/sm.cpp

@@ -103,6 +103,8 @@ void SM::GetService(Kernel::HLERequestContext& ctx) {
         rb.Push(client_port.Code());
         LOG_ERROR(Service_SM, "called service=%s -> error 0x%08X", name.c_str(),
                   client_port.Code().raw);
+        if (name.length() == 0)
+            return; // LibNX Fix
         UNIMPLEMENTED();
         return;
     }