Adds option to disable the randr KCM (to use KScreen instead) wrt bug #524266.

Source: http://pkgs.fedoraproject.org/cgit/kde-workspace.git/plain/kde-workspace-4.10.2-BUILD_KCM_RANDR.patch

diff -up kde-workspace-4.10.2/kcontrol/CMakeLists.txt.BUILD_KCM_RANDR kde-workspace-4.10.2/kcontrol/CMakeLists.txt
--- kde-workspace-4.10.2/kcontrol/CMakeLists.txt.BUILD_KCM_RANDR	2013-03-01 00:32:25.040847159 -0600
+++ kde-workspace-4.10.2/kcontrol/CMakeLists.txt	2013-04-18 08:58:31.086753204 -0500
@@ -6,9 +6,10 @@ macro_log_feature(FREETYPE_FOUND "FreeTy
 set(libkxftconfig_SRCS ${CMAKE_CURRENT_SOURCE_DIR}/fonts/kxftconfig.cpp )
 
 
-if( X11_Xrandr_FOUND )
+OPTION(BUILD_KCM_RANDR "Build kcontrol/randr module" ON)
+if(BUILD_KCM_RANDR AND X11_Xrandr_FOUND)
    add_subdirectory( randr )
-endif(X11_Xrandr_FOUND )
+endif(BUILD_KCM_RANDR AND X11_Xrandr_FOUND)
 
 if(X11_Xkb_FOUND)
     add_subdirectory( keyboard )