[PATCH] net: apple: mace: Fix build since dev_addr constification

[Jakub Kicinski]

On Fri, 14 Jan 2022 14:12:52 +1100 Michael Ellerman wrote:
> Since commit adeef3e32146 ("net: constify netdev->dev_addr") the mace
> driver no longer builds with various errors (pmac32_defconfig):
> 
>   linux/drivers/net/ethernet/apple/mace.c: In function ‘mace_probe’:
>   linux/drivers/net/ethernet/apple/mace.c:170:20: error: assignment of read-only location ‘*(dev->dev_addr + (sizetype)j)’
>     170 |   dev->dev_addr[j] = rev ? bitrev8(addr[j]): addr[j];
>         |                    ^
>   linux/drivers/net/ethernet/apple/mace.c: In function ‘mace_reset’:
>   linux/drivers/net/ethernet/apple/mace.c:349:32: warning: passing argument 2 of ‘__mace_set_address’ discards ‘const’ qualifier from pointer target type
>     349 |     __mace_set_address(dev, dev->dev_addr);
>         |                             ~~~^~~~~~~~~~
>   linux/drivers/net/ethernet/apple/mace.c:93:62: note: expected ‘void *’ but argument is of type ‘const unsigned char *’
>      93 | static void __mace_set_address(struct net_device *dev, void *addr);
>         |                                                        ~~~~~~^~~~
>   linux/drivers/net/ethernet/apple/mace.c: In function ‘__mace_set_address’:
>   linux/drivers/net/ethernet/apple/mace.c:388:36: error: assignment of read-only location ‘*(dev->dev_addr + (sizetype)i)’
>     388 |  out_8(&mb->padr, dev->dev_addr[i] = p[i]);
>         |                                    ^
> 
> Fix it by making the modifications to a local macaddr variable and then
> passing that to eth_hw_addr_set(), as well as adding some missing const
> qualifiers.
> 
> Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>

Reviewed-by: Jakub Kicinski <kuba at kernel.org>