[libc++] Remove unnecessary reinterpret_cast from typeinfo

[Jonathan.Crowther]

Summary

In typeinfo there is a reinterpret_cast between a uintptr_t and size_t. These are two integer types and therefore a reinterpret_cast is not right for this situation. It looks like it may have been copied and pasted from above in the file. An implicit cast works in it's place.

libcxx/include/typeinfo

struct __non_unique_arm_rtti_bit_impl {
     _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE
     static __type_name_t __string_to_type_name(const char* __v) _NOEXCEPT {
       return reinterpret_cast<__type_name_t>(__v);
     }
 
     _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE
     static size_t __hash(__type_name_t __v) _NOEXCEPT {
       if (__is_type_name_unique(__v))
-        return reinterpret_cast<size_t>(__v);
+        return __v;
       return __non_unique_impl::__hash(__type_name_to_string(__v));
     }
     _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE
     static bool __eq(__type_name_t __lhs, __type_name_t __rhs) _NOEXCEPT {
       if (__lhs == __rhs)
         return true;
       if (__is_type_name_unique(__lhs) || __is_type_name_unique(__rhs))
         // Either both are unique and have a different address, or one of them