llvm/CMakeLists.txt: Fix LLVM_LIT_TOOLS_DIR since r143728. Cygwin does not...

llvm/CMakeLists.txt: Fix LLVM_LIT_TOOLS_DIR since r143728. Cygwin does not need optional tools dir. MSVC and mingw may need one.

llvm-svn: 146339

llvm/CMakeLists.txt

@@ -164,8 +164,8 @@ if (MSVC OR XCODE)
 endif()
 set(LLVM_LIT_ARGS "${LIT_ARGS_DEFAULT}" CACHE STRING "Default options for lit")
 
-# On Win32/Cygwin, provide an option to specify the path to the GnuWin32 tools.
-if( WIN32 AND CYGWIN )
+# On Win32 hosts, provide an option to specify the path to the GnuWin32 tools.
+if( WIN32 AND NOT CYGWIN )
   set(LLVM_LIT_TOOLS_DIR "" CACHE PATH "Path to GnuWin32 tools")
 endif()