The SUPPORT_SYSRQ ifdeffery is not nice as:
- May create misunderstanding about sizeof(struct uart_port) between
  different objects
- Prevents moving functions from serial_core.h
- Reduces readability (well, it's ifdeffery - it's hard to follow)
In order to remove SUPPORT_SYSRQ, has_sysrq variable has been added.
Initialise it in driver's probe and remove ifdeffery.
Signed-off-by: Dmitry Safonov <dima@arista.com>
Link: https://lore.kernel.org/r/20191213000657.931618-51-dima@arista.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  *  Based on drivers/serial/8250.c, by Russell King.
  */
 
-#if defined(CONFIG_SERIAL_VR41XX_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
-#define SUPPORT_SYSRQ
-#endif
-
 #include <linux/console.h>
 #include <linux/errno.h>
 #include <linux/init.h>
                port = &siu_uart_ports[i];
                port->ops = &siu_uart_ops;
                port->dev = &dev->dev;
+               port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_VR41XX_CONSOLE);
 
                retval = uart_add_one_port(&siu_uart_driver, port);
                if (retval < 0) {