[ Upstream commit d43810b2c1808ac865aa1a2a2c291644bf95345c ]

The return value of dma_map_single() should be checked for errors using
dma_mapping_error() and the skb has been dequeued so it needs to be
freed.

This was found when enabling CONFIG_DMA_API_DEBUG and it warned about the
missing dma_mapping_error() call.

Fixes: 1807da49 ("ath10k: wmi: add management tx by reference support over wmi")
Reported-by: NNiklas Cassel <niklas.cassel@linaro.org>
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: NKalle Valo <kvalo@codeaurora.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>