systemd: fix /var/log/journal ownership

The ownership needs to be explicitly set otherwise it inherits the user
and group id of the build user.

(From OE-Core rev: 0752c792)

Signed-off-by: Jonathan Liu <net147@gmail.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: Saul Wold <sgw@linux.intel.com>

Conflicts:
	meta/recipes-core/systemd/systemd_219.bb
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>