doc/cephadm: Revert "doc/cephadm: update about disabling logging to journald for...

doc/cephadm: Revert "doc/cephadm: update about disabling logging to journald for quincy"

This reverts commit bdb2241ca5a9758e8c52d47320d8b5ea0766aea9.

This commit https://github.com/ceph/ceph/commit/bdb2241ca5a9758e8c52d47320d8b5ea0766aea9
was updating on logging changes in quincy, but seems to have been
erroneously included in a pacific batch backport https://github.com/ceph/ceph/pull/42736

This stuff doesn't work in pacific. For example,

[ceph: root@vm-00 /]# ceph version
ceph version 16.2.13-257-gd8c5d349 (d8c5d34975dce1c5eb0aa3a7979a4d9b9a99d1ec) pacific (stable)
[ceph: root@vm-00 /]# ceph config set global log_to_journald false
Error EINVAL: unrecognized config option 'log_to_journald'

so we shouldn't have it in the pacific docs

Signed-off-by: Adam King <adking@redhat.com>