Enable aarch64 and ppc64le builds

[jjhelmus]

The arch migrator is waiting for pyqt to be build for these platforms but this is unnecessary if a different backend, such as tk, is used on these platforms.

Checklist

• Used a 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.

[jjhelmus]

@conda-forge-admin, please rerender

[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.

[jjhelmus]

Note that I did not bump the build number here as this adding new packages for the linux-ppc64le ad linux-aarch64 platforms. Not change is made to the existing packages on other platforms.

[jjhelmus]

The rerender did not add the new platforms as build targets. I'll look into this a bit later as these need to be added for this PR to have the desired effect.

[jjhelmus]

The linux-ppc64le builds are failing with the following:

Traceback (most recent call last):
  File "/home/conda/feedstock_root/build_artifacts/matplotlib-base_1566951056194/test_tmp/run_test.py", line 29, in <module>
    import matplotlib.backends._tkagg
ImportError: libX11.so.6: cannot open shared object file: No such file or directory

It seems as if the X11 libraries need to be installed into the ppc64le build image for this recipe. I do not see anything in the logs indicating that dependencies in yum_requirements.txt are being installed on this platform. Is something different required for ppc64le?

[dopplershift]

mesa-libGL I think pulls it in I believe.

[isuruf]

This was fixed in conda-smithy. Need a rerender and a merge conflict resolve

[dopplershift]

@conda-forge-admin please rerender

[conda-forge-linter]

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

I was trying to look for recipes to lint for you, but it appears we have a merge conflict.
Please try to merge or rebase with the base branch to resolve this conflict.

Please ping the 'conda-forge/core' team (using the @ notation in a comment) if you believe this is a bug.

[dopplershift]

Well, it was worth a shot. 😁

[hadim]

Please see #223

[dopplershift]

Superseded by #223 .