[CMAKE] Initialize variables before their output.

The overview after 'cmake .' was called often contained 'holes',
i.e., output from variables that were not initialized. I changed
this by initializing the variables.

diff --git a/CMakeLists.txt b/CMakeLists.txt
index da1fce5..ea6d1be 100644 (file)
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -226,9 +226,11 @@ include(CheckIncludeFiles)
 include(CheckLibraryExists)
 include(CheckSymbolExists)
 
+set(HAVE_GRAPHVIZ 0)
 include(FindGraphviz)
 include(FindLibSigc++)
 
+set(HAVE_LUA 0)
 if(enable_lua)
   include(FindLuaSimgrid)
 endif()