add adaptive_avg_pool2d

[kiya00]

Before submitting

• Was this discussed/approved via a Github issue? (no need for typos and docs improvements)
• Did you read the contributor guideline, Pull Request section?
• Did you make sure to update the docs?
• Did you write any new necessary tests?

What does this PR do?

Fixes #346 .

[kiya00]

Hi @nikitaved , I fixed the test case, could you help to take a look again

[nikitaved]

Sorry for the delay, now I am back! LGTM! Thank you :)

[kiya00]

Hi @t-vi @mruberry , could you also take a look if it can be merged

[mruberry]

Awesome, @kiya00! I made some small comments for your review.

@IvanYashchuk would you like to take a look at this, too?

[IvanYashchuk]

Let's move the meta functions from prims.py to the torch file and remove the prims.* functions. They don't add any value since it's a rather direct path from thunder.torch.adaptive_avg_pool2d -> thunder.prims.adaptive_avg_pool2d.

Once it's done let's merge it.

[kiya00]

Hi @t-vi @carmocca , I think it's ready to merge, the failures come from the known distributed case issue

[t-vi]

Thank you @kiya00 @nikitaved @IvanYashchuk @mruberry