free can't be executed when strdup "" in function getAddressFromInterface

[YeHuiSheng]

In the funciton getAddressFromInterface, clstr_iface_name maybe point to strdup "" in get_clstr_iface.
When clstr_iface_name is point to strdup "", it is not null, but it's lenth is 0.
Then a little memory will be leaked because free won't be executed.
The strlen judgement need to be moved.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/671952

[OpenStack Infra (hudson-openstack)]

Change abandoned by YeHuiSheng (<email address hidden>) on branch: master
Review: https://review.opendev.org/671952

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/671999

[Ghada Khalil (gkhalil)]

Low priority / not gating - code cleanup without any noted functional impact

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/671999
Committed: https://git.openstack.org/cgit/starlingx/metal/commit/?id=f945697f26f92bcd42f569868015d18ff04a1304
Submitter: Zuul
Branch: master

commit f945697f26f92bcd42f569868015d18ff04a1304
Author: YeHuiSheng <email address hidden>
Date: Mon Jul 22 17:15:27 2019 +0800

    Modify the strlen judgement to avoid memory leak.

    Change-Id: I4752ba24943b4c5e47e63b3c3e95811dec73ecce
    Closes-Bug: #1837344
    Signed-off-by: YeHuiSheng <email address hidden>