libxc: Fix compilation after distribution changes

[RemiLacroix-IDRIS]

Probably a side effect of a change on Gitlab side.

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[RemiLacroix-IDRIS]

I have changed this PR to a draft as it seems that the problem is more complex than I initially realized.

[RemiLacroix-IDRIS]

Removed the WIP tag, I have pushed a new commit which fixes all the issues.

[RemiLacroix-IDRIS]

@alalazo: I should have updated the description of this PR with the content of my new commit message:

libxc: Fix compilation after distribution changes.

The release tarballs are not available anymore which means autoconf, automake and libtool are always needed.

The NVHPC specific patches don't make sense anymore being that the patched files are not distributed in the new tar files.