genirq: Fix for_each_action_of_desc() macro

struct irq_desc does not have a member named "act".  The correct
name is "action".

Currently, all users of this macro use an iterator named "action".
If a different name is used, it will cause a build error.

Fixes: f944b5a7 ("genirq: Use a common macro to go through the actions list")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1502260341-28184-1-git-send-email-yamada.masahiro@socionext.com