[PATCH] powerpc: Revised merge asm-ppc*/hardirq.h

This is a revised patch to merge asm-ppc*/hardirq.h.
It removes some unnecessary #includes, but then requires
the addition of #include <asm/irq.h> in PPC32's hw_irq.h
much like ppc64 already does.  Furthermore, several
unnecessary #includes were removed from some ppc32 boards
in order to break resulting bad #include cycles.

Builds pSeries_defconfig and all ppc32 platforms except
the already b0rken bseip.

Signed-off-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>