net: marvell10g: soft-reset the PHY when coming out of low power

Soft-reset the PHY when coming out of low power mode, which seems to
be necessary with firmware versions 0.3.3.0 and 0.3.10.0.

This depends on ("net: marvell10g: report firmware version")

Fixes: c9cc1c81

 ("net: phy: marvell10g: place in powersave mode at probe")
Reported-by: Matteo Croce <mcroce@redhat.com>
Tested-by: Matteo Croce <mcroce@redhat.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>