iwlwifi: move ucode_type from iwl_priv to iwl_shared

Move the ucode_type variable from the iwl_priv to the iwl_shared
structure with associated code changes.

Signed-off-by: Don Fry <donald.h.fry@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>