cli: Fix no libxml compilation for snapshot status

BUG: 1122186
Change-Id: Ib887f2194258e85d40f65a758b6a963a17911395
Signed-off-by: Kaushal M <kaushal@redhat.com>
Reviewed-on: http://review.gluster.org/8363
Reviewed-by: Rajesh Joseph <rjoseph@redhat.com>
Reviewed-by: Santosh Pradhan <spradhan@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Atin Mukherjee <amukherj@redhat.com>