iwlwifi: mvm: Take the phy_cfg from the TLV value

The phy_cfg is given from the TLV value and does not have to be
built by us.

Signed-off-by: Dor Shaish <dor.shaish@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>