usb: usbtest: fix NULL pointer dereference

If the usbtest driver encounters a device with an IN bulk endpoint but
no OUT bulk endpoint, it will try to dereference a NULL pointer
(out->desc.bEndpointAddress).  The problem can be solved by adding a
missing test.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Reported-by: NAndrey Konovalov <andreyknvl@google.com>
Tested-by: NAndrey Konovalov <andreyknvl@google.com>
Signed-off-by: NFelipe Balbi <felipe.balbi@linux.intel.com>

drivers/usb/misc/usbtest.c

@@ -202,12 +202,13 @@ get_endpoints(struct usbtest_dev *dev, struct usb_interface *intf)
 			return tmp;
 	}
 
-	if (in) {
+	if (in)
 		dev->in_pipe = usb_rcvbulkpipe(udev,
 			in->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
+	if (out)
 		dev->out_pipe = usb_sndbulkpipe(udev,
 			out->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
-	}
+
 	if (iso_in) {
 		dev->iso_in = &iso_in->desc;
 		dev->in_iso_pipe = usb_rcvisocpipe(udev,