The axienet_start_xmit() returns NETDEV_TX_OK without freeing skb
in case of dma_map_single() fails, add dev_kfree_skb_any() to fix it.

Fixes: 71791dc8 ("net: axienet: Check for DMA mapping errors")
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
Link: https://patch.msgid.link/20241014143704.31938-1-wanghai38@huawei.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>