Description of problem:
When running iscsiadm -m discovery -p "127.0.0.1" -o delete, the target portal is deleted, but the current sessions are not removed.


Version-Release number of selected component (if applicable):
iscsi-initiator-utils-6.2.0.872-34.el6.x86_64

How reproducible:
100%

Steps to Reproduce:
1. install scsi-target-utils
2. service tgtd restart
3. tgtadm --lld iscsi --op new --mode target --tid 1 -T
iqn.1994-05.com.redhat:tgtd-1
4. tgtadm --lld iscsi --op bind --mode target --tid 1 -I ALL
5. Create disk for LUN: mktemp /tmp/disk.XXXXX
        dd if=/dev/zero of=/tmp/disk.XXXXX bs=1M count=0 seek=100
6. tgtadm --lld iscsi --op new --mode logicalunit --tid 1 --lun 1 -b
/tmp/disk.XXXXX

7.iscsiadm -m discovery -t st -p "127.0.0.1" -I default -P1
8. iscsiadm -m node -l
9. iscsiadm -m discovery -p "127.0.0.1" -o delete
10.iscsiadm -m session
tcp: [124] 127.0.0.1:3260,1 iqn.1994-05.com.redhat:tgtd-1

11. iscsiadm -m session --sid 124
iscsiadm: No records found
12. iscsiadm -m node -p 127.0.0.1 --logout
Logging out of session [sid: 124, target: iqn.1994-05.com.redhat:tgtd-1,
portal: 127.0.0.1,3260]
Logout of [sid: 124, target: iqn.1994-05.com.redhat:tgtd-1, portal:
127.0.0.1,3260] successful.

Actual results:
Target portal deleted, but session exists.

Expected results:
I'd expect an error when trying to delete the portal when there is still sessions like that:
iscsiadm -m node -T iqn.1994-05.com.redhat:tgtd-1 -o delete
iscsiadm: This command will remove the record [iface: default, target: iqn.1994-05.com.redhat:tgtd-1, portal: 127.0.0.1,3260], but a session is using it. Logout session then rerun command to remove record.
iscsiadm: Could not execute operation on all records: session exists


Or the sessions would also be removed.