TTY: 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: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/tty/hvc/hvcs.c b/drivers/tty/hvc/hvcs.c
index e523773..55882b5 100644
--- a/drivers/tty/hvc/hvcs.c
+++ b/drivers/tty/hvc/hvcs.c
@@ -1057,7 +1057,7 @@
 	 * the conn was registered and now.
 	 */
 	if (!(rc = request_irq(irq, &hvcs_handle_interrupt,
-				IRQF_DISABLED, "ibmhvcs", hvcsd))) {
+				0, "ibmhvcs", hvcsd))) {
 		/*
 		 * It is possible the vty-server was removed after the irq was
 		 * requested but before we have time to enable interrupts.