$ git clone -n https://src.fedoraproject.org/rpms/mame.git /var/lib/mock/f38-build-side-42-init-devel-1283320-30672/root/chroot_tmpdir/scmroot/mame
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-1283320-30672/root/chroot_tmpdir/scmroot/mame'...
$ git fetch origin d4203a75f313a057d3005af0bfdbe30f27fd7264:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/mame
 * [new ref]         d4203a75f313a057d3005af0bfdbe30f27fd7264 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d4203a7 Update to 0.258