powerpc/5200: Don't specify IRQF_SHARED in PSC UART driver

The MPC5200 PSC device is wired up to a dedicated interrupt line
which is never shared.  This patch removes the IRQF_SHARED flag
from the request_irq() call which eliminates the "IRQF_DISABLED
is not guaranteed on shared IRQs" warning message from the console
output.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Reviewed-by: NWolfram Sang <w.sang@pengutronix.de>

drivers/serial/mpc52xx_uart.c

@@ -522,7 +522,7 @@ mpc52xx_uart_startup(struct uart_port *port)
 
 	/* Request IRQ */
 	ret = request_irq(port->irq, mpc52xx_uart_int,
-		IRQF_DISABLED | IRQF_SAMPLE_RANDOM | IRQF_SHARED,
+		IRQF_DISABLED | IRQF_SAMPLE_RANDOM,
 		"mpc52xx_psc_uart", port);
 	if (ret)
 		return ret;