[PATCH] 'mdio_bus_exit' in discarded section .text.exit

When building with  CONFIG_PHYLIB=y on Itanium, I see:
 `mdio_bus_exit' referenced in section `.init.text' of
drivers/built-in.o: defined in discarded section `.exit.text' of
drivers/built-in.o

I believe that mdio_bus_exit should not be declared __exit, because it is
referencesd from __init sections in, say, phy_init().

Signed-off-by: Peter Chubb <peterc@gelato.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>