On the commit 4c8660d, we dropped /usr/lib/scylla/jmx since it likely no user
script invoke scripts under the directory.
However, we found there are possibility scylla-jmx.service tries to load .jar
file from /usr/lib/scylla/jmx, when user upgraded from older version of scylla.
Because /etc/sysconfig/scylla-jmx is marked as 'noreplace' on our rpm,
yum upgrade may keep old sysconfig file when it modified by user, that may
causes to load .jar from /usr/lib/scylla/jmx since we specify the path in the
sysconfig file.
To avoid the issue it's better to have symlinks on /usr/lib/scylla/jmx for
safety.
See #90
46681753cd