Make .desktop file executable.
Make .desktop file executable.

Improves compatibility.

Task-number: QTIFW-301
Change-Id: I648071075fd802a5e9b8ff248b423849125b0d74
Reviewed-by: Tim Jenssen <6a21f175c697b4129e1bafb6e9b52078bb1a6738@digia.com>

olear/qtifw,olear/qtifw,olear/qtifw,olear/qtifw