xf86/logind: Fix drm_drop_master before vt_reldisp
When switching to VT, the ioctl DRM_DROP_MASTER must be done before the ioctl VT_RELDISP. So before doing the VT_RELDISP, send a dbus message to logind, to pause the drm device, so logind will do the ioctl DRM_DROP_MASTER.
With this patch, it changes the order logind will send the resume event, and drm will be sent last instead of first. So there is a also fix to call systemd_logind_vtenter() at the right time.