The spec file is changed based with which exacted from glusterfs-10.0.tar.gz.
Following changes are made:
* make variable _with_systemd true as default
* make variable _usepython3 as 1
* make variable _pythonver as 2
* remove fedora_koji_builds judgements
* add new BuildRequires: rpcgen gperftools-devel libunwind-devel
* update source0 to following address
https://download.gluster.org/pub/gluster/glusterfs/10/10.0/glusterfs-10.0.tar.gz
Signed-off-by: Wenchao Hao <haowenchao@huawei.com>