[Applet]Add port check
Summary:
Add port check before port.description check.
Cannot check port.description if port does not exist.
Test Plan:
Before:
If there is a device with ports, and an other one without ports, will fail to display the name a device, or crash?
After:
Name should be displayed correctly in every case.
Reviewers: Plasma, drosca, ngraham
Reviewed By: ngraham
Subscribers: plasma-devel
Tags: Plasma
Differential Revision: https://phabricator.kde.org/D27074