PGMYUV seems to be always limited range. This was a format originally
invented by FFmpeg at a time when YUVJ distinguished limited from full
range YUV, and this codec never appeared to output YUVJ in any
circumstance, so hard-coding limited range preserves the status quo.
The other formats are explicitly documented to be full range RGB/gray
formats. That said, don't tag them yet, due to outstanding bugs w.r.t
grayscale formats and color range handling.
This change in behavior updates a bunch of FATE tests in trivial ways
(added tagging being the only difference).
* commit 'f8df5e2f31a5ba7b30a0e1caaaf5a03c753b3f9b':
tests: Add a convenience function for video-only lavf tests
Merged-by: James Almer <jamrial@gmail.com>