CMake: fixed configure of applications if TUTTLE_PYTHON_VERSION is not defined

Author: Clement Champetier

applications/CMakeLists.txt

@@ -4,6 +4,10 @@ add_subdirectory(sam)
 # scripts
 add_subdirectory(script)
 
+if(NOT TUTTLE_PYTHON_VERSION)
+    return()
+endif()
+
 # Edit python scripts if the host is built with python3
 if(${TUTTLE_PYTHON_VERSION} VERSION_GREATER "3")
     set(BASH_PYTHON2 "#!/usr/bin/env python")