remove unused variable

Change-Id: I2221adf838f4c33ae279705ad93141ebce30338e
Reviewed-by: Jake Petroules <jake.petroules@petroules.com>
Reviewed-by: Christian Kandeler <christian.kandeler@digia.com>
remove dead code from GenericGCC.qbs

This is a copy & paste artifact and does nothing
due to the wrong usage of Array.concat.

Change-Id: Ie99bcecacba5be0e167b661d4e4bc5ce18c09189
Reviewed-by: Christian Kandeler <christian.kandeler@digia.com>