Don't use T as template argument, it is part of the application

namespace.


git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@195693 91177308-0d34-0410-b5e6-96231b3b80d8

include/ext/__hash

@@ -19,7 +19,7 @@
 namespace __gnu_cxx {
 using namespace std;
 
-template <typename T> struct _LIBCPP_TYPE_VIS_ONLY hash : public std::hash<T>
+template <typename _Tp> struct _LIBCPP_TYPE_VIS_ONLY hash : public std::hash<_Tp>
     { };
 
 template <> struct _LIBCPP_TYPE_VIS_ONLY hash<const char*>