iwlagn: move check_stuck_queue to transport layer

This one is really transport related.

==== moves Stanislaw's code to BSD area ====

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>