Disarm check for usable TUN/TAP file. On Genode the DrvTAP is implemented
by network.cc and uses Genode nic_session directly.

--- a/src/virtualbox6/src/VBox/Main/src-client/ConsoleImpl2.cpp
+++ b/src/virtualbox6/src/VBox/Main/src-client/ConsoleImpl2.cpp
@@ -5255,18 +5255,24 @@
                                             "sure that these changes are permanent, especially if you are "
                                             "using udev"));
                         default:
+#if 0
                             AssertMsgFailed(("Could not attach to host interface! Bad!\n"));
                             return VMSetError(VMR3GetVM(mpUVM), VERR_HOSTIF_INIT_FAILED, RT_SRC_POS, N_(
                                             "Failed to initialize Host Interface Networking"));
+#else
+                            break;
+#endif
                     }
                 }
 
+#if 0
                 Assert((intptr_t)maTapFD[uInstance] >= 0);
                 if ((intptr_t)maTapFD[uInstance] >= 0)
+#endif
                 {
                     InsertConfigString(pLunL0, "Driver", "HostInterface");
                     InsertConfigNode(pLunL0, "Config", &pCfg);
-                    InsertConfigInteger(pCfg, "FileHandle", (intptr_t)maTapFD[uInstance]);
+                    InsertConfigInteger(pCfg, "Slot", uInstance);
                 }
 
 #elif defined(VBOX_WITH_NETFLT)
