bug#25514: SDDM segfaults X11 session on first reconfigure

[ng0]

I noticed this:

My system uses SLIM.
I build the new system config which includes SDDM instead,
reconfigure, and at the point where SDDM service probably gets
started, SDDM segfaults the current X11 session.

This is a grave error with SDDM and needs some better way of
handling the initial activation of the new display manager.
-- 
♥Ⓐ  ng0 -- https://www.inventati.org/patternsinthechaos/