This update for sddm fixes the following issues:

- Add SLE branding package for PackageHub (boo#1101297)

- Change the Supplements of branding packages, so they get installed
  when sddm and the respective branding package is installed. Also
  added a Supplements to sddm so it gets recommended when
  plasma5-workspace is installed.

- Provide a sddm-branding-SLE package with correct dependencies,
  together with sddm-branding-openSUSE (boo#1025387, boo#1069396)