avcodec/hevc_ps: fix 1 vs. 0 typo

Found-by: Timothy Gu <timothygu99@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/hevc_ps.c

@@ -472,7 +472,7 @@ static void decode_vui(HEVCContext *s, HEVCSPS *sps)
     VUI *vui          = &sps->vui;
     GetBitContext *gb = &s->HEVClc->gb;
     GetBitContext backup;
-    int sar_present, alt = 1;
+    int sar_present, alt = 0;
 
     av_log(s->avctx, AV_LOG_DEBUG, "Decoding VUI\n");