$ git clone -n https://src.fedoraproject.org/rpms/vlc.git /var/lib/mock/f42-build-side-1-3589270-46955/root/chroot_tmpdir/scmroot/vlc
Cloning into '/var/lib/mock/f42-build-side-1-3589270-46955/root/chroot_tmpdir/scmroot/vlc'...
$ git fetch origin aa1a2ca368ebe3d16ff55d087389126f47870e1c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/vlc
 * [new ref]         aa1a2ca368ebe3d16ff55d087389126f47870e1c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at aa1a2ca Enable faad2