Make hard_irq_disable() actually hard-disable interrupts

commit f948501b36c6b3d9352ce212a197098a7e958971 upstream.

At present, hard_irq_disable() does nothing on powerpc because of
this code in include/linux/interrupt.h:

    #ifndef hard_irq_disable
    #define hard_irq_disable()      do { } while(0)
    #endif

So we need to make our hard_irq_disable be a macro.  It was previously
a macro until commit 7230c56441 ("powerpc: Rework lazy-interrupt
handling") changed it to a static inline function.

Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--
 arch/powerpc/include/asm/hw_irq.h |    3 +++
 1 file changed, 3 insertions(+)