Run the cmake build as part of make distcheck.
Run the cmake build as part of make distcheck.

Verify that the CMake build works from a release tarball.
This will give coverage for problems with part of the
CMake build description not being included in the
source package. We still consider the `make dist`
output from the GNU autotools build to be canonical.

xiph/ogg,xiph/ogg,ShiftMediaProject/ogg,ShiftMediaProject/ogg