Java's position was moved.  Add workaround instructions
to use with debs built upstream (not ubuntu/debian version)

Change-Id: Ia42426aabbcfabb2ca46d811d8b742e23b33d4b6
Reviewed-on: https://gerrit.libreoffice.org/18999Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>