iwlwifi: introducing the drv object's flows

Fetch the fw and spawn the op_mode. The op_mode that we need
to fetch is determined from the fw file.
Since the fw is fetched very early in the init flow, we can
determine what op_mode to spawn.

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