powerpc/irq: Remove IRQF_DISABLED

Since commit [e58aa3d2: genirq: Run irq handlers with interrupts disabled],
We run all interrupt handlers with interrupts disabled
and we even check and yell when an interrupt handler
returns with interrupts enabled (see commit [b738a50a:
genirq: Warn when handler enables interrupts]).

So now this flag is a NOOP and can be removed.

Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Geoff Levand <geoff@infradead.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/include/asm/xics.h b/arch/powerpc/include/asm/xics.h
index bd6c401..c48de98 100644
--- a/arch/powerpc/include/asm/xics.h
+++ b/arch/powerpc/include/asm/xics.h
@@ -15,8 +15,8 @@
 #define	DEFAULT_PRIORITY	5
 
 /*
- * Mark IPIs as higher priority so we can take them inside interrupts that
- * arent marked IRQF_DISABLED
+ * Mark IPIs as higher priority so we can take them inside interrupts
+ * FIXME: still true now?
  */
 #define IPI_PRIORITY		4