Recent opencv API changes break upstream filter and example.
Make opencv explicitly configurable.

Upstream-Status: Inappropriate [configuration]

Signed-off-by: Tim Orling <TicoTimo@gmail.com>

Index: vlc-2.1.4/configure.ac
===================================================================
--- vlc-2.1.4.orig/configure.ac
+++ vlc-2.1.4/configure.ac
@@ -1693,7 +1693,16 @@ PKG_ENABLE_MODULES_VLC([BLURAY], [libblu
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 dnl  OpenCV wrapper and example filters
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-PKG_ENABLE_MODULES_VLC([OPENCV], [opencv_example opencv_wrapper], [opencv > 2.0], (OpenCV (computer vision) filter), [auto])
+AC_ARG_ENABLE(opencv,
+  [AS_HELP_STRING([--disable-opencv],
+    [disable OpenCV computer vision filter and example (default auto)])])
+if test "${enable_opencv}" != "no"
+then
+    PKG_ENABLE_MODULES_VLC([OPENCV], 
+                           [opencv_example opencv_wrapper], 
+                           [opencv > 2.0], 
+                           (OpenCV (computer vision) filter), [auto])
+fi
 
 
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