vdpau: Add missing #includes to fix standalone header compilation

Signed-off-by: Anton Khirnov <anton@khirnov.net>

libavcodec/vdpau.h

@@ -52,6 +52,10 @@
 #include <vdpau/vdpau.h>
 #include <vdpau/vdpau_x11.h>
 
+#include "libavutil/attributes.h"
+
+#include "version.h"
+
 #if FF_API_BUFS_VDPAU
 union AVVDPAUPictureInfo {
     VdpPictureInfoH264        h264;

libavcodec/vdpau_internal.h

@@ -26,8 +26,10 @@
 
 #include <stdint.h>
 #include <vdpau/vdpau.h>
-#include "h264.h"
+
+#include "avcodec.h"
 #include "mpegvideo.h"
+#include "version.h"
 
 /** Extract VdpVideoSurface from a Picture */
 static inline uintptr_t ff_vdpau_get_surface_id(Picture *pic)
@@ -42,6 +44,8 @@ union AVVDPAUPictureInfo {
     VdpPictureInfoVC1          vc1;
     VdpPictureInfoMPEG4Part2 mpeg4;
 };
+#else
+#include "vdpau.h"
 #endif
 
 struct vdpau_picture_context {