Fix vm_migrate_task statemachine_task_status value.

[tinaafitz]

Check status to determine return value.

Depends on: ManageIQ/manageiq#15332

https://bugzilla.redhat.com/show_bug.cgi?id=1422961

[tinaafitz]

@miq-bot assign @gmcculloug
@miq-bot add_label bug, fine/yes

[miq-bot]

Checked commit tinaafitz@aaf998e with ruby 2.2.6, rubocop 0.47.1, and haml-lint 0.20.0
2 files checked, 0 offenses detected
Everything looks fine. 👍

[gmcculloug]

Opened issue #39 to address code client duplication issue.

[simaishi]

Fine backport (to manageiq repo) details:

$ git log -1
commit c3d20fa84f18371729a486c0b4bfe22443d446d5
Author: Greg McCullough <gmccullo@redhat.com>
Date:   Thu Jun 8 15:51:18 2017 -0400

    Merge pull request #38 from tinaafitz/vm_migrate_fix
    
    Fix vm_migrate_task statemachine_task_status value.
    (cherry picked from commit f4bc749a055b9fff6b215ad62b83263fba29327b)
    
    https://bugzilla.redhat.com/show_bug.cgi?id=1479478