ARM: shmobile: Lager: add Micrel KSZ8041 PHY fixup

Currently on the Lager board NFS timeouts/delays are seen when booting.  That
turned out to happen because the SoC's ETH_LINK signal turns on and off after
each packet.  It is connected to Micrel KSZ8041 PHY's LED0 signal. Ether LEDs
on the Lager board are named LINK and ACTIVE which corresponds to non-default
01 setting of the PHY control register 1 bits 14-15. The 'sh_eth' driver resets
the PHY when opening the network device, so we have to set the mentioned bits
back to 01 from the default 00 value which causes bouncing of ETH_LINK.  That
can be achieved using the PHY platform fixup mechanism if we also modify the
driver to use it..

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>