kshortcutschemeseditor: Fix unstranslatable Default scheme name
For the "Default" scheme, put the translation as the display role and "Default" in the data role. Put the other scheme names put their name as both the display name and data role.
For the "Default" scheme, put the translation as the display role and "Default" in the data role. Put the other scheme names put their name as both the display name and data role.