Add vllm v0.21.0 build script

[Akashcodes732]

Checklist

• Have you checked and followed all the points mention in the CONTRIBUTING.MD
• Have you validated script on UBI 9 container
• [x ] Did you run the script(s) on fresh container with set -e option enabled and observe success ?
• [NA] Did you have Legal approvals for patch files ?

[janani66]

@Akashcodes732 -- do you need to install the required version of pillow explicity like it is done in https://github.com/ppc64le/build-scripts/blob/master/v/vllm/vllm_v0.16.0_ubi_9.6.sh#L132 ?

[Akashcodes732]

Hi @janani66,

@Akashcodes732 -- do you need to install the required version of pillow explicity like it is done in https://github.com/ppc64le/build-scripts/blob/master/v/vllm/vllm_v0.16.0_ubi_9.6.sh#L132 ?

Did this, but now there are issues with other packages.

For different python version, looks like there is issue with different packages (some because the package version for all python version is not available on devpi).

Currently its passing for python 3.{11,12,13}.
Can we go ahead with wheels for these three versions.