Start using stdlib('c') in recipes

[isuruf]

conda-forge is using these to be explicit about the sysroot version and bioconda should too.

cc @mbargull

[martin-g]

We tried to add it in one of the recipes but it failed to lint: #51295 (comment)
https://dev.azure.com/bioconda/bioconda-recipes/_build/results?buildId=71416&view=logs&j=eb1ca712-fec5-5d93-deb0-40983fe61f2f&t=c9ebc308-e058-58af-a4f4-866fa7649dbb&l=39

CC @mfansler

[aliciaaevans]

I am at a conference this week, but I will plan to take a look next week at what needs to be changed in the linting. (But if anyone else wants to submit a PR to bioconda-utils, please feel free.)