patch-avidemux__plugins_CMakeLists.txt

--- avidemux_plugins/CMakeLists.txt.orig	2019-08-15 09:25:40.000000000 +0200
+++ avidemux_plugins/CMakeLists.txt	2020-01-10 15:07:57.924344000 +0100
@@ -265,7 +265,9 @@
 ADD_SUBDIRECTORY(ADM_videoEncoder)
 ADD_SUBDIRECTORY(ADM_videoFilters6)
 IF(DO_QT4)
+    IF(NOT DO_COMMON)
         add_subdirectory(ADM_demuxers/VapourSynth)
+    ENDIF(NOT DO_COMMON)
     #    add_subdirectory(ADM_scriptEngines)
         #IF(USE_OPENGL AND NOT WIN32)
         IF(USE_OPENGL )