[PATCH] spidernet: read firmware from the OF device tree

request_firmware() is sometimes problematic, especially
in initramfs, reading the firmware from Open Firmware
is much preferrable.

We still try to get the firmware from the file system
first, in order to support old SLOF releases and to allow
updates of the spidernet firmware without reflashing
the system.

From: Jens Osterkamp <Jens.Osterkamp@de.ibm.com>
Signed-off-by: Jens Osterkamp <Jens.Osterkamp@de.ibm.com>
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>