iwlwifi: code cleanup for generic defines

Some defines used by all agn devices, but the definitions were in
iwl-4965-hw.h, move those to iwl-agn-hw.h which is the better place for
those.

Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-agn.c b/drivers/net/wireless/iwlwifi/iwl-agn.c
index 8b66010..ef5690a 100644
--- a/drivers/net/wireless/iwlwifi/iwl-agn.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn.c
@@ -3368,7 +3368,7 @@
 	/* Set the tx_power_user_lmt to the lowest power level
 	 * this value will get overwritten by channel max power avg
 	 * from eeprom */
-	priv->tx_power_user_lmt = IWL_TX_POWER_TARGET_POWER_MIN;
+	priv->tx_power_user_lmt = IWLAGN_TX_POWER_TARGET_POWER_MIN;
 
 	ret = iwl_init_channel_map(priv);
 	if (ret) {