drivers: net: cpsw: abort init() on aneg timeout

drivers: net: cpsw: abort init() on aneg timeout

Abort CPSW driver init when auto-negotiation of link
times out. Currently, the code ignores return status
of phy_startup(), and goes ahead with network operation
(like DHCP) even though the link may be down.

Instead, abort init process if link is down or if there
is another error, so phy_startup() can easily be retried
again. This also helps quick fallback to next network interface
(like USB RNDIS) without inordinate delay.

Tested on AM571x IDK and AM335x BeagleBone black.

Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>