net: mv643xx_eth: disable clk on error path in mv643xx_eth_shared_probe()

[ Upstream commit e928b5d6b75e239feb9c6d5488974b6646a0ebc8 ]

If mv643xx_eth_shared_of_probe() fails, mv643xx_eth_shared_probe()
leaves clk enabled.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>