lavfi/drawutils: improve colorspace support

[rcombs]

This introduces ff_draw_init2, adding support for colorspaces other than BT601 and explicit full/limited range configuration.

[ffmpeg-codebot]

There is an issue in commit bd1d5b7:
Commit not signed off

[ffmpeg-codebot]

There are issues in commit a16b7a3:
Please wrap lines in the body of the commit message between 60 and 72 characters.
Commit not signed off

[rcombs]

/submit

[ffmpeg-codebot]

Error: Ignoring PR with empty title and/or body

[rcombs]

/submit

[ffmpeg-codebot]

There is an issue in commit bd1d5b7:
Commit not signed off

[ffmpeg-codebot]

There are issues in commit a16b7a3:
Please wrap lines in the body of the commit message between 60 and 72 characters.
Commit not signed off

[softworkz]

There are issues in commit a16b7a3: Please wrap lines in the body of the commit message between 60 and 72 characters. Commit not signed off

Do you think I should drop this check?

But then it would go yellow on Patchwork (like this: https://patchwork.ffmpeg.org/project/ffmpeg/patch/20220602055636.3585381-1-wenbin.chen@intel.com/)

[rcombs]

/submit

[ffmpeg-codebot]

There is an issue in commit d80e1b2:
Please wrap lines in the body of the commit message between 60 and 72 characters.

[ffmpeg-codebot]

There is an issue in commit d80e1b2:
Please wrap lines in the body of the commit message between 60 and 72 characters.

[rcombs]

/submit

[ffmpeg-codebot]

Submitted as pull.33.ffstaging.FFmpeg.1654192626.ffmpegagent@gmail.com

To fetch this version into FETCH_HEAD:

git fetch https://github.com/ffstaging/FFmpeg pr-ffstaging-33/rcombs/drawutils-v1

To fetch this version to local tag pr-ffstaging-33/rcombs/drawutils-v1:

git fetch --no-tags https://github.com/ffstaging/FFmpeg tag pr-ffstaging-33/rcombs/drawutils-v1

[softworkz]

merged upstream