Otherwise hotplugging the PEX doesn't work at all since the driver
detects the link state at probe time. Simply replacing the two tests
of haslink with a register read is enough to fix it.

Tested on kirkwood with repeated plug/unplug of the link partner.
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Acked-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>