[maguro] Remove tmpfiles for Jolla Startupwizard

The actual issue has been fixed and depends on the following
fix for the QPA hwcomposer v1.0 backend:

https://github.com/mer-hybris/qt5-qpa-hwcomposer-plugin/pull/27

Change-Id: I21a825219e13e953cea8b43db8087e629b268fe3