Cosmetic patch simplifying the smi read and write error paths. It also
align their error paths with the ones of the xsmi functions.
Signed-off-by: NAntoine Tenart <antoine.tenart@free-electrons.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>