linux-phytec-ti

iwlwifi: define and use if iwl_mvm_has_tlc_offload

This aligns the code with the existing pattern to check
if the firmware has a certain capability.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>