Render DRM-PRIME frames as opaque images

We can't always assume they are NV12. Even if they _are_ NV12,
they may have DRM format modifiers that are incompatible with
simply assuming linear Y and UV buffers (such as tiling).

app/streaming/video/ffmpeg-renderers/eglvid.h

@@ -55,6 +55,7 @@ private:
 #define NV12_PARAM_OFFSET 1
 #define NV12_PARAM_PLANE1 2
 #define NV12_PARAM_PLANE2 3
+#define OPAQUE_PARAM_TEXTURE 0
     int m_ShaderProgramParams[4];
 
 #define OVERLAY_PARAM_TEXTURE 0