Add osqp support

[traversaro]

Fix #51 . Uses casadi/casadi#2671 by @GiulioRomualdi .

Checklist

• Used a personal fork of the feedstock to propose changes
• Bumped the build number (if the version is unchanged)
• Reset the build number to 0 (if the version changed)
• Re-rendered with the latest conda-smithy (Use the phrase @conda-forge-admin, please rerender in a comment in this PR for automated rerendering)
• Ensured the license file is being packaged.

[conda-forge-linter]

Hi! This is the friendly automated conda-forge-linting service.

I just wanted to let you know that I linted all conda-recipes in your PR (recipe) and found it was in an excellent condition.

[traversaro]

@conda-forge-admin, please rerender

[github-actions]

Hi! This is the friendly automated conda-forge-webservice.
I tried to rerender for you, but it looks like I wasn't able to push to the patch-6
branch of traversaro/casadi-feedstock. Did you check the "Allow edits from maintainers" box?

NOTE: PRs from organization accounts cannot be rerendered because of GitHub
permissions.

[pariterre]

LGTM!
Good job! Should I merge?

[traversaro]

LGTM!
Good job! Should I merge?

Thanks! Yes it seems ready to be merged.