net: phy: Improved PHY error reporting in state machine

When the PHY library calls phy_error() something bad has happened, and
we halt the PHY state machine. Calling phy_error() from the main state
machine however is not precise enough to know whether the issue is
reading the link status or starting auto-negotiation.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>