iwlwifi: don't WARN on host commands sent when firmware is dead

This triggers automatic bug reports and add no valuable
information. Print a simple error instead and drop the
host command.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

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

@@ -601,8 +601,10 @@ static inline int iwl_trans_send_cmd(struct iwl_trans *trans,
 {
 	int ret;
 
-	WARN_ONCE(trans->state != IWL_TRANS_FW_ALIVE,
-		  "%s bad state = %d", __func__, trans->state);
+	if (trans->state != IWL_TRANS_FW_ALIVE) {
+		IWL_ERR(trans, "%s bad state = %d", __func__, trans->state);
+		return -EIO;
+	}
 
 	if (!(cmd->flags & CMD_ASYNC))
 		lock_map_acquire_read(&trans->sync_cmd_lockdep_map);