MIPS: SGI-IP27: remove ioc3 ethernet init

Removed not needed disabling of ethernet interrupts in IP27 platform code.

Acked-by: Paul Burton <paul.burton@mips.com>
Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>