usbip: list: don't list devices attached to vhci_hcd

usbip host lists devices attached to vhci_hcd on the same server
when user does attach over localhost or specifies the server as the
remote.

usbip attach -r localhost -b busid
or
usbip attach -r servername (or server IP)

Fix it to check and not list devices that are attached to vhci_hcd.

Cc: [e-mail]
Signed-off-by: Shuah Khan <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

tools/usb/usbip/src/usbip_list.c

···
 	const char *busid;
 	char product_name[128];
 	int ret = -1;
+	const char *devpath;
 
 	/* Create libudev context. */
 	udev = udev_new();
···
 	udev_list_entry_foreach(dev_list_entry, devices) {
 		path = udev_list_entry_get_name(dev_list_entry);
 		dev = udev_device_new_from_syspath(udev, path);
+
+		/* Ignore devices attached to vhci_hcd */
+		devpath = udev_device_get_devpath(dev);
+		if (strstr(devpath, USBIP_VHCI_DRV_NAME)) {
+			dbg("Skip the device %s already attached to %s\n",
+			    devpath, USBIP_VHCI_DRV_NAME);
+			continue;
+		}
 
 		/* Get device information. */
 		idVendor = udev_device_get_sysattr_value(dev, "idVendor");