Added a simple way to collect XFS information

Signed-off-by: Pierguido Lambri <plambri@redhat.com>
Changed the source part of the sos.spec

Signed-off-by: Pierguido Lambri <plambri@redhat.com>
Fixed indentation issue

Signed-off-by: Pierguido Lambri <plambri@redhat.com>