irqchip: bcm7120-l2: Convert driver to use irq_reg_{readl,writel}

On BE MIPS systems this needs to use the new IRQ_GC_BE_IO gc_flag.  In
all other cases it will use the standard readl/writel accessors.

The initial irq_fwd_mask setup runs before "gc" is initialized, so it
is unchanged for now.  This could potentially be a problem on an ARM
system that boots in LE mode but runs a BE kernel, but currently none
of the supported ARM platforms are ever expected to run BE.

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lkml.kernel.org/r/1415342669-30640-14-git-send-email-cernekee@gmail.com


Signed-off-by: Jason Cooper <jason@lakedaemon.net>