Follow up with info block changed in new qemu V2

Change log to v1:
      1. fix call get_block_old with self.
      2. fix 4 lines indentation off in  qemu/tests/cdrom.py.

In qemu monitor, 'info block' has changed, the old style is:
info block
scsi0-hd0: removable=0 io-status=ok file=
./autotest/client/tests/virt/shared/data/images/f18-64.qcow2 ro=0
drv=qcow2 encrypted=0 bps=0 bps_rd=0 bps_wr=0 iops=0 iops_rd=0
iops_wr=0
scsi0-cd1: removable=1 locked=1 tray-open=0 io-status=ok file=
./autotest/client/tests/virt/shared/data/images/orig.iso ro=1
drv=raw encrypted=0 bps=0 bps_rd=0 bps_wr=0 iops=0 iops_rd=0
iops_wr=0

But the in new qemu with the commit id:
fbe2e26
info block
drive-virtio-disk1: ./autotest/client/tests/virt/shared/
data/images/f18-64.qcow2 (qcow2)

drive-ide0-0-0: ./autotest/client/tests/virt/shared/
data/images/orig.iso (raw, read-only)
Removable device: locked, tray closed

This two patches, make autotest to support the new qemu .
Signed-off-by: Mike Qiu qiudayu@linux.vnet.ibm.com