Code cleanup related to license handling

[Ghada Khalil]

Brief Description
-----------------
There is code in starlingx related to license handling that is failing. This code was left-over from the original code base since the beginning of the project. This code should be cleaned up to handle the lack of licenses gracefully.

Severity
--------
Minor - code cleanup

Steps to Reproduce
------------------
Run system license-install

Expected Behavior
------------------
Command fails with a missing library

Actual Behavior
----------------
Command should do nothing given there are no license requirements for starlingx

Reproducibility
---------------
Reproudcible

System Configuration
--------------------
N/A

Branch/Pull Time/Commit
-----------------------
master since day 1

Last Pass
---------
N/A

Timestamp/Logs
--------------
N/A

Test Activity
-------------
Other - code review

[Ghada Khalil (gkhalil)]

Minor as this is related to code cleanup

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/685397

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/685394
Committed: https://git.openstack.org/cgit/starlingx/config/commit/?id=54f164a193708d603d6f3dfe5a4ceff62a8eac9c
Submitter: Zuul
Branch: master

commit 54f164a193708d603d6f3dfe5a4ceff62a8eac9c
Author: Bin Qian <email address hidden>
Date: Fri Sep 27 12:06:30 2019 -0400

    Clean up licensing code

    Remove "system license-list" command,
    replace with "system license-show"
    The new system license-show command shows the content of the
    license file

    Remove any validation and interpretation of license file.

    Partial-Bug: 1845522
    Change-Id: I9dfb765d300e86eae1c554703e8e3e4f088d87b7
    Signed-off-by: Bin Qian <email address hidden>

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/685397
Committed: https://git.openstack.org/cgit/starlingx/utilities/commit/?id=f45ec23405754c35f1a58950f8043d14c355dfbf
Submitter: Zuul
Branch: master

commit f45ec23405754c35f1a58950f8043d14c355dfbf
Author: Bin Qian <email address hidden>
Date: Fri Sep 27 12:12:21 2019 -0400

    Clean up license code

    Remove any license verification and interpretation.

    Closes-Bug: 1845522
    Change-Id: I1ca264311bc8ea0d828ea01c890220641a20e6a5
    Signed-off-by: Bin Qian <email address hidden>