Remove an outdated comment
Remove an outdated comment

We're now marking the tiff loader as threadsafe, so
remove the comment that says it isn't.

YueLinHo/MB3Gdk-pixbuf,GNOME/gdk-pixbuf,Distrotech/gdk-pixbuf,GNOME/gdk-pixbuf,YueLinHo/MB3Gdk-pixbuf,YueLinHo/MB3Gdk-pixbuf,Distrotech/gdk-pixbuf,Distrotech/gdk-pixbuf,YueLinHo/MB3Gdk-pixbuf,GNOME/gdk-pixbuf,Distrotech/gdk-pixbuf,YueLinHo/MB3Gdk-pixbuf,GNOME/gdk-pixbuf,Distrotech/gdk-pixbuf