[Fedora-packaging] New dynamic macro for tracking fpc (Free Pascal Compiler) supported architectures

Hi, I've created a new draft proposal on https://fedorahosted.org/fpc/ticket/608 It would be nice to have a new dynamic macro for tracking fpc (Free Pascal Compiler) supported architectures. Currently all packages which depend on fpc to build must list in the .spec file the ExclusiveArch entry. Having an ExclusiveArch: %{fpc_arches} macro would be easier and future proof since in future there will be no need of manual intervention if fpc will become available on more architectures. This has been proposed in a recent review request https://bugzilla.redhat.com/show_bug.cgi?id=1299127#c6 Thanks Mattia