--vpp-subburn causes subs to be half size and to the left

[cdgriffith]

Only tested on 4K videos so far, but using just --vpp-subburn track=2 causes the track to be small and over to the left.

Example command:

"VCEEncC64.exe" --avhw -i "movie.mkv" --video-metadata clear --video-metadata title="title" --chapter-copy -c hevc --cqp 18 --preset slow --tier high --colormatrix bt2020nc --transfer smpte2084 --colorprim bt2020 --master-display "G(13250,34500)B(7500,3000)R(34000,16000)WP(15635,16450)L(10000000,20)" --max-cll "595,494" --output-depth 10 --motion-est q-pel --chromaloc auto --colorrange auto --avsync cfr  --audio-metadata 1?language=eng --audio-stream 1?:2.1 --audio-codec 1?aac --audio-bitrate 1?192  --audio-metadata 1?clear --audio-metadata 1?title="2.1" --audio-metadata 1?handler="2.1"   --vpp-subburn track=2 -o "e133.mkv"