iwlwifi: handle the case when set power fail

Modify the power update function, when driver fail to set the power, it
should not continue move forward and try to change the rx chain
configuration.
Signed-off-by: NWey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: NReinette Chatre <reinette.chatre@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

drivers/net/wireless/iwlwifi/iwl-power.c

@@ -282,18 +282,21 @@ int iwl_power_update_mode(struct iwl_priv *priv, bool force)
 			cmd.flags |= IWL_POWER_FAST_PD;
 
 		ret = iwl_set_power(priv, &cmd);
-
+		if (!ret) {
 			if (final_mode == IWL_POWER_MODE_CAM)
 				clear_bit(STATUS_POWER_PMI, &priv->status);
 
-		if (priv->cfg->ops->lib->update_chain_flags && update_chains)
+			if (priv->cfg->ops->lib->update_chain_flags &&
+			    update_chains)
 				priv->cfg->ops->lib->update_chain_flags(priv);
 			else
-			IWL_DEBUG_POWER(priv, "Cannot update the power, chain noise "
+				IWL_DEBUG_POWER(priv,
+					"Cannot update the power, chain noise "
 					"calibration running: %d\n",
 					priv->chain_noise_data.state);
-		if (!ret)
 			setting->power_mode = final_mode;
+		} else
+			IWL_ERR(priv, "set power fail, ret = %d", ret);
 	}
 
 	return ret;