dxva2: fix surface selection when compiled with both d3d11va and dxva2

Fixes a regression introduced in
be630b1eSigned-off-by: Anton Khirnov <anton@khirnov.net>

libavcodec/dxva2.c

@@ -41,7 +41,7 @@ unsigned ff_dxva2_get_surface_index(const AVCodecContext *avctx,
     void *surface = ff_dxva2_get_surface(frame);
     unsigned i;
 
-    for (i = 0; i < DXVA_CONTEXT_COUNT(avctx, ctx); i++)
+    for (i = 0; i < DXVA_CONTEXT_COUNT(avctx, ctx); i++) {
 #if CONFIG_D3D11VA
         if (avctx->pix_fmt == AV_PIX_FMT_D3D11VA_VLD && ctx->d3d11va.surface[i] == surface) {
             D3D11_VIDEO_DECODER_OUTPUT_VIEW_DESC viewDesc;
@@ -53,6 +53,7 @@ unsigned ff_dxva2_get_surface_index(const AVCodecContext *avctx,
         if (avctx->pix_fmt == AV_PIX_FMT_DXVA2_VLD && ctx->dxva2.surface[i] == surface)
             return i;
 #endif
+    }
 
     assert(0);
     return 0;