matroskamux: allow resolutions above 4096

Modify the caps string to allow width and height greater than 4096.
There is no need to restrict it since the matroska format allows the
width and height values to be up to eight bytes long.

https://bugzilla.gnome.org/show_bug.cgi?id=773582

gst/matroska/matroska-mux.c

@@ -89,8 +89,8 @@ static GstStaticPadTemplate src_templ = GST_STATIC_PAD_TEMPLATE ("src",
     );
 
 #define COMMON_VIDEO_CAPS \
-  "width = (int) [ 16, 4096 ], " \
-  "height = (int) [ 16, 4096 ] "
+  "width = (int) [ 16, MAX ], " \
+  "height = (int) [ 16, MAX ] "
 
 /* FIXME:
  * * require codec data, etc as needed