net: fec: correct the error path for regulator disable in probe

[ Upstream commit c6165cf0dbb82ded90163dce3ac183fc7a913dc4 ]

Correct the error path for regulator disable.

Fixes: 9269e5560b26 ("net: fec: add phy-reset-gpios PROBE_DEFER check")
Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>