net: ethernet: stmmac: fix documentation warning

This patch remove the following documentation warning
drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c:103: warning: Excess function parameter 'priv' description in 'stmmac_axi_setup'
It was introduced in commit afea03656add7 ("stmmac: rework DMA bus setting and introduce new platform AXI structure")

Signed-off-by: Corentin Labbe <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c

···
 /**
  * stmmac_axi_setup - parse DT parameters for programming the AXI register
  * @pdev: platform device
- * @priv: driver private struct.
  * Description:
  * if required, from device-tree the AXI internal register can be tuned
  * by using platform parameters.