libusb: depend on actual host-libtool binary

We need to depend on the actual host-libtool binary instead of the phony
host-libtool as libusb otherwise will get recompiled every time.

package/libusb/libusb.mk

@@ -24,7 +24,7 @@ $(DL_DIR)/$(LIBUSB_SOURCE): $(LIBUSB_PATCH)
 libusb-source: $(DL_DIR)/$(LIBUSB_SOURCE) $(LIBUSB_PATCH)
 
 libusb-unpacked: $(LIBUSB_DIR)/.unpacked
-$(LIBUSB_DIR)/.unpacked: $(AUTOCONF) $(AUTOMAKE) host-libtool $(DL_DIR)/$(LIBUSB_SOURCE)
+$(LIBUSB_DIR)/.unpacked: $(AUTOCONF) $(AUTOMAKE) $(STAGING_DIR)/$(LIBTOOL_TARGET_BINARY) $(DL_DIR)/$(LIBUSB_SOURCE)
 	$(LIBUSB_CAT) $(DL_DIR)/$(LIBUSB_SOURCE) | tar -C $(BUILD_DIR) $(TAR_OPTIONS) -
 ifneq ($(LIBUSB_PATCH_FILE),)
 	(cd $(LIBUSB_DIR) && $(LIBUSB_CAT) $(LIBUSB_PATCH) | patch -p1)