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/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 2ec57b2..ca1a4c3 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -1961,7 +1961,7 @@
 	 * For the muxed case there's nothing more to do.
 	 */
 	port->irq		= p->irqs[SCIx_RXI_IRQ];
-	port->irqflags		= IRQF_DISABLED;
+	port->irqflags		= 0;
 
 	port->serial_in		= sci_serial_in;
 	port->serial_out	= sci_serial_out;