iwlwifi: remove duplicate iwlagn_mod_params declaration

We only need one declaration, not multiple.
Keep the one in iwl-shared.h, which will
probably be renamed to iwl-modparams.h at
some point in the future.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>

drivers/net/wireless/iwlwifi/iwl-dev.h

@@ -1019,7 +1019,6 @@ struct iwl_priv {
 }; /*iwl_priv */
 
 extern struct kmem_cache *iwl_tx_cmd_pool;
-extern struct iwl_mod_params iwlagn_mod_params;
 
 static inline struct iwl_rxon_context *
 iwl_rxon_ctx_from_vif(struct ieee80211_vif *vif)