MIPS: RB532: Fix devices.c compilation.

We should now use dev_set_drvdata to set the driver driver_data field.

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/747/


Signed-off-by: Ralf Baechle <ralf@linux-mips.org>