arm-soc: sparse IRQ conversion

The I.MX platform is getting converted to use sparse IRQs. We are doing
this for all platforms over time, because this is one of the
requirements for building a multiplatform kernel, and generally a good
idea.
Merge branch 'imx/sparse-irq' of git://git.linaro.org/people/shawnguo/linux-2.6 into next/irq

Two bug fixes for the previous state of the imx sparse irq changes.

* 'imx/sparse-irq' of git://git.linaro.org/people/shawnguo/linux-2.6:
  ARM: imx: select USE_OF
  ARM: imx: Fix build error due to missing irqs.h include

Signed-off-by: Arnd Bergmann <arnd@arndb.de>