Fix ffi issue

[isuruf]

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.

Fixes #522
Closes #523
Closes #524

[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.

[isuruf]

@conda-forge-admin, rerender

[github-actions]

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

I considered the following status checks when analyzing this PR:

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

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

[h-vetinari]

One of the travis builds for this failed after merging - could someone restart it?

[h-vetinari]

Thanks for restarting!

Also: awesome work by lots of people in terms of connecting many different dots. 🥳

[mbargull]

Also: awesome work by lots of people in terms of connecting many different dots. partying_face

Very much agreed! Thanks to everyone involved for digging up everything to get to the button and fixing this!