V4L/DVB (10055): em28xx: Add entry for PixelView PlayTV Box 4

Added board PixelView PlayTV Box 4
Thanks to Vildenei Negrao Pereira <neodarkaman@brturbo.com.br> for testing and data collection.

Signed-off-by: Douglas Schilling Landgraf <dougsland@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/Documentation/video4linux/CARDLIST.em28xx b/Documentation/video4linux/CARDLIST.em28xx
index 0c4c721..96b1eb8 100644
--- a/Documentation/video4linux/CARDLIST.em28xx
+++ b/Documentation/video4linux/CARDLIST.em28xx
@@ -59,3 +59,4 @@
  58 -> Compro VideoMate ForYou/Stereo           (em2820/em2840) [185b:2041]
  59 -> Pinnacle PCTV HD Mini                    (em2874)        [2304:023f]
  60 -> Hauppauge WinTV HVR 850                  (em2883)        [2040:651f]
+ 61 -> Pixelview PlayTV Box 4 USB 2.0           (em2820/em2840)