Add protection from min/max macros

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@145407 91177308-0d34-0410-b5e6-96231b3b80d8

include/regex

@@ -732,6 +732,8 @@ typedef regex_token_iterator<wstring::const_iterator> wsregex_token_iterator;
 #include <vector>
 #include <deque>
 
+#include <__undef_min_max>
+
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header
 #endif