[media] dvb_usb_v2: move dvb_usbv2_generic_rw() debugs behind define

It is nice to have this debug, but as it generates very huge amount
of traffic, better to make it conditional. Use define macro to disable
it as I did not find out how to use dynamic debugs to dump variable
length buffers like that.
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/dvb/dvb-usb/dvb_usb_urb.c

@@ -8,6 +8,7 @@
  */
 #include "dvb_usb_common.h"
 
+#undef DVB_USB_XFER_DEBUG
 int dvb_usbv2_generic_rw(struct dvb_usb_device *d, u8 *wbuf, u16 wlen, u8 *rbuf,
 	u16 rlen, int delay_ms)
 {
@@ -26,8 +27,10 @@ int dvb_usbv2_generic_rw(struct dvb_usb_device *d, u8 *wbuf, u16 wlen, u8 *rbuf,
 	if (ret)
 		return ret;
 
+#ifdef DVB_USB_XFER_DEBUG
 	print_hex_dump(KERN_DEBUG, KBUILD_MODNAME ": >>> ", DUMP_PREFIX_NONE,
 			32, 1, wbuf, wlen, 0);
+#endif
 
 	ret = usb_bulk_msg(d->udev, usb_sndbulkpipe(d->udev,
 			d->props->generic_bulk_ctrl_endpoint), wbuf, wlen,
@@ -53,10 +56,10 @@ int dvb_usbv2_generic_rw(struct dvb_usb_device *d, u8 *wbuf, u16 wlen, u8 *rbuf,
 		if (ret)
 			pr_err("%s: recv bulk message failed: %d\n",
 					KBUILD_MODNAME, ret);
-		else
-			print_hex_dump(KERN_DEBUG, KBUILD_MODNAME ": <<< ",
-					DUMP_PREFIX_NONE, 32, 1, rbuf, actlen,
-					0);
+#ifdef DVB_USB_XFER_DEBUG
+		print_hex_dump(KERN_DEBUG, KBUILD_MODNAME ": <<< ",
+				DUMP_PREFIX_NONE, 32, 1, rbuf, actlen, 0);
+#endif
 	}
 
 	mutex_unlock(&d->usb_mutex);