obs-ffmpeg: Set P3-D65 metadata for HDR

Want to avoid receiver gamut remapping from Rec. 2100 to P3.

Fix min luminance appearing as NaN by switching from 0/0 to 0/1.

Also set max luminance for HLG because why not.

plugins/obs-ffmpeg/obs-ffmpeg-mux.c

@@ -163,7 +163,8 @@ static void add_video_encoder_params(struct ffmpeg_muxer *stream,
 						: AVCOL_RANGE_MPEG;
 
 	const int max_luminance =
-		(trc == AVCOL_TRC_SMPTE2084)
+		((trc == AVCOL_TRC_SMPTE2084) ||
+		 (trc == AVCOL_TRC_ARIB_STD_B67))
 			? (int)obs_get_video_hdr_nominal_peak_level()
 			: 0;