opengl: fix possible typo

There isn't a case where program[0] is 0 and program[1] is 0. They are always
created together. So the second part of the if() is never called.

program[0] is for YUV and XYZ sources so it is odd to use it with a single
planar texture, given that's what program[1] is for.
Signed-off-by: Thomas Guillem <thomas@gllm.fr>

modules/video_output/opengl.c

@@ -1689,7 +1689,7 @@ int vout_display_opengl_Display(vout_display_opengl_t *vgl,
     }
 
 #ifdef SUPPORTS_SHADERS
-    if (vgl->program[0] && (vgl->chroma->plane_count == 3 || vgl->chroma->plane_count == 1))
+    if (vgl->program[0] && (vgl->chroma->plane_count == 3 || vgl->chroma->plane_count == 2))
         DrawWithShaders(vgl, left, top, right, bottom, 0);
     else if (vgl->program[1] && vgl->chroma->plane_count == 1)
         DrawWithShaders(vgl, left, top, right, bottom, 1);