qcacmn: Add missed error handling in dp_tx_send_msdu_single

If there is anything wrong, the caller of dp_tx_send_msdu_single
will only handle skb free, but not skb unmapping. So inside of
dp_tx_send_msdu_single, it is needed to make sure unmap operation
is performed after map operation.

CRs-Fixed: 2358266
Change-Id: I6379305e84f70b5b978e9504b758c7a6ccf328ee
1 file changed