Merge commit 'b8962d64'

* commit 'b8962d64':
  dxva2: Clean up definition of _WIN32_WINNT

Conflicts:
	libavcodec/dxva2.h

See: 89946c84Merged-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/dxva2.h

@@ -29,11 +29,8 @@
  * Public libavcodec DXVA2 header.
  */
 
-#if defined(_WIN32_WINNT) && _WIN32_WINNT < 0x0600
+#if !defined(_WIN32_WINNT) || _WIN32_WINNT < 0x0600
 #undef _WIN32_WINNT
-#endif
-
-#if !defined(_WIN32_WINNT)
 #define _WIN32_WINNT 0x0600
 #endif