atheroswifi: try at fixing #8351

* ath introduced an inconsistency between driver module name and driver_t name
  which the compat layer uses to lookup driver symbol
* we now use ath_pci instead of ath as driver_t name member.
* trace a message when a symbol can't be found during driver module search.

src/add-ons/kernel/drivers/network/wlan/atheroswifi/dev/ath/if_ath_pci.c

@@ -245,7 +245,11 @@ static device_method_t ath_pci_methods[] = {
 	{ 0,0 }
 };
 static driver_t ath_pci_driver = {
+#ifdef __HAIKU__
+	"ath_pci",
+#else
 	"ath",
+#endif
 	ath_pci_methods,
 	sizeof (struct ath_pci_softc)
 };

src/libs/compat/freebsd_network/compat.c

@@ -323,8 +323,10 @@ device_add_child(device_t parent, const char *name, int unit)
 			snprintf(symbol, sizeof(symbol), "__fbsd_%s_%s", name,
 				parent->driver->name);
 			if (get_image_symbol(find_own_image(), symbol, B_SYMBOL_TYPE_DATA,
-					(void **)&driver) == B_OK)
+					(void **)&driver) == B_OK) {
 				child = new_device(*driver);
+			} else
+				device_printf(parent, "couldn't find symbol %s\n", symbol);
 		}
 	} else
 		child = new_device(NULL);