Help: Remove workaround for pre-CMake 2.8.4 code.

The requirement was updated in commit 920ffbf5 (Require CMake 2.8.4
or greater to build CMake, 2013-10-11) and similar snippets were
removed.

Utilities/Sphinx/CMakeLists.txt

@@ -11,8 +11,7 @@
 #=============================================================================
 if(NOT CMake_SOURCE_DIR)
   set(CMakeHelp_STANDALONE 1)
-  cmake_minimum_required(VERSION 2.8.2 FATAL_ERROR)
-  set(CMAKE_LEGACY_CYGWIN_WIN32 0) # Remove when CMake >= 2.8.4 is required
+  cmake_minimum_required(VERSION 2.8.4 FATAL_ERROR)
   get_filename_component(tmp "${CMAKE_CURRENT_SOURCE_DIR}" PATH)
   get_filename_component(CMake_SOURCE_DIR "${tmp}" PATH)
   include(${CMake_SOURCE_DIR}/Modules/CTestUseLaunchers.cmake)