um: 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>
Signed-off-by: Richard Weinberger <richard@nod.at>
diff --git a/arch/um/kernel/time.c b/arch/um/kernel/time.c
index 82a6e22..d1a23fb 100644
--- a/arch/um/kernel/time.c
+++ b/arch/um/kernel/time.c
@@ -82,7 +82,7 @@
 {
 	int err;
 
-	err = request_irq(TIMER_IRQ, um_timer, IRQF_DISABLED, "timer", NULL);
+	err = request_irq(TIMER_IRQ, um_timer, 0, "timer", NULL);
 	if (err != 0)
 		printk(KERN_ERR "register_timer : request_irq failed - "
 		       "errno = %d\n", -err);