net: bcmgenet: abort suspend on error

[ Upstream commit c5a54bbcececa36852807c36157a86d808b62310 ]

If an error occurs during suspension of the driver the driver should
restore the hardware configuration and return an error to force the
system to resume.

Fixes: 0db55093b566 ("net: bcmgenet: return correct value 'ret' from bcmgenet_power_down")
Signed-off-by: Doug Berger <opendmb@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>