contrib: gnutls: Add patch to fix .pc file on Darwin
This is a patch of c19cb93d492e45141bfef9b926dfeba36003261c which is currently in GnuTLS next branch. It fixes the .pc file to include missing frameworks in Libs.private, fixing the build of some VLC modules that depend on GnuTLS or have GnuTLS as transitive dependency.
Edited by Marvin Scholz