ARM: 8234/1: sa1100: reorder IRQ handling code

This patch just reorders functions/data inside sa1100 irq driver to be
able to merge functions that have the same code after converting to
irqdomains and hwirq. No real code changes.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>