dist/common/scripts/scylla_selinux_setup: keep symlink on /etc/sysconfig/selinux
dist/common/scripts/scylla_selinux_setup: keep symlink on /etc/sysconfig/selinux

Current script has a bug that overwrites symlink on
/etc/sysconfig/selinux by real file, the script not able to disable
SELinux because of it.

So keep symlink after modifying the file.

Fixes #2279

Signed-off-by: Takuya ASADA <4ebfb6f510af412d6e89fefa3ab96d9c8b5e3fff@scylladb.com>
Message-Id: <1493663263-10573-1-git-send-email-4ebfb6f510af412d6e89fefa3ab96d9c8b5e3fff@scylladb.com>

avikivity/scylla,scylladb/scylla,duarten/scylla,scylladb/scylla,duarten/scylla,scylladb/scylla,duarten/scylla,scylladb/scylla,avikivity/scylla,avikivity/scylla