Adding osqp-eigen recipe

[GiulioRomualdi]

Checklist

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The PR is ready to be reviewed @conda-forge/help-c-cpp

This PR closes #15080
cc @traversaro

[conda-forge-linter]

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

I wanted to let you know that I linted all conda-recipes in your PR (recipes/osqp-eigen) and found some lint.

Here's what I've got...

For recipes/osqp-eigen:

• Selectors are suggested to take a <two spaces>#<one space>[<expression>] form. See lines [28, 29, 30, 31]

For recipes/osqp-eigen:

• License is not an SPDX identifier (or a custom LicenseRef) nor an SPDX license expression.

Documentation on acceptable licenses can be found here.

[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 (recipes/osqp-eigen) and found it was in an excellent condition.

[conda-forge-linter]

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

I wanted to let you know that I linted all conda-recipes in your PR (recipes/stable-baselines3) and found some lint.

Here's what I've got...

For recipes/stable-baselines3:

• Feedstock with the same name exists in conda-forge.

[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 (recipes/osqp-eigen) and found it was in an excellent condition.

[traversaro]

@GiulioRomualdi feel free to add me as well as maintainer, it is a good practice to avoid having just one maintainer in recipes to reduce the bus factor.

[traversaro]

The PR is ready to be reviewed @conda-forge/help-c-cpp

The CI is now green, @conda-forge/help-c-cpp this is now ready for review.

[traversaro]

@wolfv just FYI, this is the first package that we migrate from the robotology channel to conda-forge, hopefully many will follow in the future. : )

[wolfv]

Awesome!