Add a "domfsinfo" command that shows a list of filesystems info mounted in
the guest. For example:
virsh # domfsinfo vm1
Mountpoint Name Type Target
-------------------------------------------------------------------
/ sda1 ext4 hdc
/opt dm-2 vfat vda,vdb
/mnt/test sdb1 xfs sda
Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama@hds.com>