The rate scaling and the transport need to access the data in
iwl_tid_data, hence the move.

Note that the only component in the upper layer that needs this data
is the rate scaling. Refactoring the rate scaling may help to move
iwl_tid_data from the shared area to the transport 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>