x11/stalonetray: Update to 1.5.0

Add cmocka to build dependencies.
The port uses xrandr.

Changelogs:
https://github.com/d3adb5/stalonetray/releases/tag/1.3.0
https://github.com/d3adb5/stalonetray/releases/tag/1.4.0
https://github.com/d3adb5/stalonetray/releases/tag/1.5.0