ath10k: remove DMA mapping wrappers

[Dan Carpenter]

Hello Michal Kazior,

The patch 767d34fc67af: "ath10k: remove DMA mapping wrappers" from
Feb 27, 2014, leads to the following static checker warning:

	drivers/net/wireless/ath/ath10k/htt_tx.c:445 ath10k_htt_mgmt_tx()
	warn: dma_mapping_error() doesn't return an error code

drivers/net/wireless/ath/ath10k/htt_tx.c
   443          skb_cb->paddr = dma_map_single(dev, msdu->data, msdu->len,
   444                                         DMA_TO_DEVICE);
   445          res = dma_mapping_error(dev, skb_cb->paddr);
   446          if (res)
   447                  goto err_free_txdesc;
   448  

We should be returning an error code here instead of 1.  There are
several of these bugs.

drivers/net/wireless/ath/ath10k/htt_tx.c:530 ath10k_htt_tx() warn: dma_mapping_error() doesn't return an error code
drivers/net/wireless/ath/ath10k/pci.c:1667 ath10k_pci_hif_exchange_bmi_msg() warn: dma_mapping_error() doesn't return an error code
drivers/net/wireless/ath/ath10k/htc.c:147 ath10k_htc_send() warn: dma_mapping_error() doesn't return an error code

regards,
dan carpenter