Set up a rc branch for 4.1.1rc1

[leofang]

Following CFEP-05.

Checklist

• [x] Used a personal fork of the feedstock to propose changes
• [ ] Bumped the build number (if the version is unchanged)
• [x] Reset the build number to 0 (if the version changed)
• [x] Re-rendered with the latest conda-smithy (Use the phrase code>@<space/conda-forge-admin, please rerender in a comment in this PR for automated rerendering)
• [x] 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.

[leofang]

@conda-forge-admin, please rerender

[github-actions[bot]]

Hi! This is the friendly automated conda-forge-webservice. I tried to rerender for you, but it looks like there was nothing to do.

[github-actions[bot]]

Hi! This is the friendly conda-forge automerge bot!

I considered the following status checks when analyzing this PR:

• linter: passed
• drone: passed
• travis: passed
• azure: passed

Thus the PR was passing and merged! Have a great day!

[leofang]

Hi @jsquyres forgot to ping you here: in response to your earlier suggestion in https://github.com/open-mpi/ompi/issues/8306#issuecomment-753371478, I set up a new rc branch targeting Open MPI's release candidates. The main purpose is to make use of Conda-Forge's CI infrastructure to test building and running the package, but if users are brave enough they can also install the rc versions via conda install -c conda-forge/label/openmpi_rc openmpi.

The only limitation is that our bot cannot automatically discover new rc releases (which it can for the official releases), so this part is manual.