The libexec path is different for different distributions.
systemd. This path is defined by a new variable on the
configure path.
This variable can be set with enviroment SYSTEMD_LIBEXEC_DIR.
The parameter --with-systemd-libexec-dir overrides the enviroment
variable.
Appropriate conditionals are set for SUSE and RHEL derivatives.
This is then used to template out systemd/ceph-osd@.service
Signed-off-by: Owen Synge <osynge@suse.com>
