shared.cfg: Add guest RHEL-5.9

rhel-server-5.9-i386-dvd.iso   e47da2a9b05a97cea5663a30642ecdd4
rhel-server-5.9-x86_64-dvd.iso 83e601da2282073aef3fcbd03b50802f
Signed-off-by: NQingtang Zhou <qzhou@redhat.com>