serial: mcf: add sysrq capability

After some unsuccessful attempts to use sysrq over console, figured
out that port->has_sysrq should likely be enabled, as per other
architectures, this when CONFIG_SERIAL_MCF_CONSOLE is also enabled.

Tested some magic sysrq commands (h, p, t, b), they works now
properly. Commands works inside 5 secs after BREAK is sent, as
expected.

Signed-off-by: Angelo Dureghello <[e-mail]>
Signed-off-by: Greg Ungerer <[e-mail]>

drivers/tty/serial/mcf.c

···
 		port->ops = &mcf_uart_ops;
 		port->flags = UPF_BOOT_AUTOCONF;
 		port->rs485_config = mcf_config_rs485;
+		port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_MCF_CONSOLE);
 
 		uart_add_one_port(&mcf_driver, port);
 	}