compile-feature detection finally corrected

AMDiS/cmake/enable_cxx11.cmake

@@ -7,7 +7,7 @@ if (ENABLE_CXX11)
         set(CMAKE_CXX_STANDARD_REQUIRED ON)
         set(REQUIRED_CXX_FEATURES "cxx_alias_templates" "cxx_auto_type" "cxx_lambdas" "cxx_override" "cxx_range_for" "cxx_static_assert" "cxx_variadic_templates")
 	
-	add_library(test_compiler_features dummy.cc)
+	add_library(test_compiler_features cmake/dummy.cc)
 	foreach(feature ${REQUIRED_CXX_FEATURES})
 	    target_compile_features(test_compiler_features PUBLIC ${feature})
         endforeach(feature)