Fix WinRT detection.

WINAPI_FAMILY_ONE_PARTITION is no longer defined in newer
Windows SDKs.

asio/include/asio/detail/config.hpp

diff --git a/asio/include/asio/detail/config.hpp b/asio/include/asio/detail/config.hpp
index f7f027a..9d7bd52 100644
--- a/asio/include/asio/detail/config.hpp
+++ b/asio/include/asio/detail/config.hpp
@@ -521,9 +521,11 @@
 #if !defined(ASIO_WINDOWS_RUNTIME)
 # if defined(__cplusplus_winrt)
 #  include <winapifamily.h>
-#  if WINAPI_FAMILY_ONE_PARTITION(WINAPI_FAMILY, WINAPI_PARTITION_APP)
+#  if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP) \
+   && !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP)
 #   define ASIO_WINDOWS_RUNTIME 1
-#  endif // WINAPI_FAMILY_ONE_PARTITION(WINAPI_FAMILY, WINAPI_PARTITION_APP)
+#  endif // WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP)
+         // && !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP)
 # endif // defined(__cplusplus_winrt)
 #endif // !defined(ASIO_WINDOWS_RUNTIME)