[SERIAL] Fix UPF_ flag usage with uart_info->flags

The previous change found a bug in the serial SAK handling - because
we were looking for UPF_SAK set in uart_info->flags, we would never
raise a SAK condition.  UPF_SAK is in uart_port->flags.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 90f6817..1a8cd01 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -430,7 +430,7 @@
 		port->sysrq = 0;
 	}
 #endif
-	if (info->flags & UPF_SAK)
+	if (port->flags & UPF_SAK)
 		do_SAK(info->tty);
 	return 0;
 }