coordination of DCAP provider packages

Since there are going to be multiple deb/rpm packages attempting to provide the libdcap_quoteprov.so shared library, does it make sense to coordinate among them somehow to prevent conflicts?

One option is to pick some virtual package name (like dcap-quote-provider or libsgx-dcap-qpl), and have each of the quote provider packages declare in its package metadata that it `Provides` and `Conflicts` with the quote provider virtual package. This will prevent installing multiple quote providers simultaneously.

A slightly more complicated option (at least for Debian-derived systems) is to use the dpkg "alternatives" system to enable the sysadmin to configure which of multiple installed quote providers should be active as the default.